JP2003035461A - Refrigerating cycle equipment and air-conditioning equipment for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide refrigerating cycle equipment and air-conditioning equipment for a vehicle which enable control of return of lubricating oil for a compressor without lowering reliability, by making use of functional components other than the compressor in the refrigerating cycle equipment. SOLUTION: Expansion valves 19 and 32 and evaporators 15 and 28 are disposed in a pair, in a plurality and in parallel respectively, in a course through which a refrigerant flows from a condenser 17 toward the compressor 16. The expansion valves 19 and 32 are temperature type ones opening and closing in accordance with the degrees of superheat of outlet refrigerants of the evaporators 15 and 28. The evaporators 15 and 28 are provided respectively with blowers 14 and 27 which make the evaporators 15 and 28 operate by blowing air thereto. In the case when at least either one evaporator 28 is in a stopped state, a first control means S100A provided in the refrigerating cycle equipment makes the blower 27 corresponding to this evaporator 28 operate for a prescribed time Tn in a prescribed cycle Ts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle apparatus having a plurality of evaporators arranged in parallel, and particularly to a front seat side air conditioning unit for air-conditioning a front seat side area of a passenger compartment and a rear passenger compartment of the passenger compartment. It is suitable to be applied to a vehicle air conditioner including a rear seat side air conditioning unit that air-conditions a seat side area.

[0002]

2. Description of the Related Art A conventional refrigeration cycle apparatus and a vehicle air conditioner are disclosed in Japanese Unexamined Patent Publication No. 2000-283576, in which a front-side evaporator serving as a main evaporator and a rear-side seat serving as a sub-evaporator. The evaporators are installed in parallel, and at least the thermal expansion valve is used as the pressure reducing means of the rear-side evaporator, and when the continuous operation time reaches a predetermined time after the start of the compressor, the low pressure pressure on the intake side of the compressor So that
It is known that the control means controls the clutch of the compressor to turn on and off a predetermined number of times after a predetermined time.

With this, the temperature type expansion valve can be forcibly opened by changing the pressure, and the lubricating oil for the compressor accumulated on the low pressure pipe side of the rear seat side evaporator by the flow of the refrigerant by the opening valve. Can be returned to the compressor, which results in
The insufficient lubrication oil return to the compressor due to the independent operation of the front seat side evaporator is eliminated, and the lubricity of the compressor can be maintained well.

[0004]

However, the compressor, which is an expensive and important functional component of the refrigeration cycle apparatus, has unsteady operation control (clutch ON-OFF repetition, that is, forced interruption control as described above). ) Is not considered a good way to ensure compressor reliability.

That is, in the above-mentioned prior art publication, while taking into consideration the durability of the compressor, the ON / OFF control in the forced interruption control is performed.
Although it is disclosed that the -OFF time and the number of times are determined, it is undeniable that the unsteady operation of the compressor is naturally increased by repeating the control itself.

In view of the above problems, the object of the present invention is to utilize the functional parts other than the compressor in the refrigeration cycle apparatus to control the return of the lubricating oil for the compressor without lowering the reliability. It is to provide a cycle device and a vehicle air conditioner.

[0007]

The present invention employs the following technical means in order to achieve the above object.

In the invention according to claim 1 relating to the refrigeration cycle apparatus, the compressor (1) for compressing the vapor phase refrigerant into high temperature and high pressure
6) and a condenser (1 for liquefying and condensing the compressed gas-phase refrigerant)
7), an expansion valve (19, 32) for expanding the liquefied and condensed refrigerant to a low temperature and low pressure, and an evaporator (15, for evaporating the expanded refrigerant and flowing it to the compressor (16)).
28) are sequentially connected to each other by a refrigerant pipe, and an expansion valve (19, 32) and an evaporator (15, 28)
Are arranged in parallel in pairs while the refrigerant flows from the condenser (17) toward the compressor (16), and each expansion valve (19, 32) is connected to each evaporator (15,
28) A thermal expansion valve (19, 32) that opens and closes according to the degree of superheat of the outlet refrigerant, and each evaporator (15, 28) includes:
In a refrigeration cycle apparatus provided with blowers (14, 27) for operating each evaporator (15, 28) by blowing air, when at least one evaporator (28) is in a stopped state. , This evaporator (28)
Is provided with a first control means (S100A) for operating the blower (27) corresponding to (1) for a predetermined time (Tn) for a predetermined period (Ts).

As a result, the blown air from the blower (27) gives a heat load to the stopped evaporator (28). Then, the temperature type expansion valve (32) is opened, the evaporator (28) is in an operating state, and the refrigerant collects this evaporator (28).
It will start to flow inside. Therefore, the evaporator (28) while stopped
The lubricating oil for the compressor that stays inside or in the low-pressure pipe (34) to the compressor (16) can be returned to the compressor (16) side.

Here, the blower (14, 27) in the refrigeration cycle device (R) is utilized to make the blower (27) on the side that is originally stopped have a predetermined period (Ts) and a predetermined time (Tn).
Only by operating it, the lubricating oil can be returned, and the reliability of the blower (27) is not deteriorated.

According to a second aspect of the invention relating to a vehicle air conditioner, a plurality of air conditioning units (1
2, 25) and the refrigeration cycle device (R) according to claim 1, and in each air conditioning unit (12, 25), an expansion valve (19, 3) of the refrigeration cycle device (R).
2), an evaporator (15, 28), and a blower (14, 27) are provided, respectively.

As a result, a plurality of air conditioning units (12,
In a vehicle air conditioner having 25), the control of the lubricating oil return utilizing the blower (14, 27) without reducing the reliability of the blower (14, 27) as in the invention according to claim 1. Correspondence becomes possible.

In the prior art, when applied to a vehicle air conditioner, signals of both the air conditioner control device for controlling the air conditioner and the engine controller for controlling the engine operating condition are normally exchanged. , Compressor (1
Since 6) is often controlled, it is necessary to change both the air-conditioning control device and the engine control device in order to newly control the compressor (16) for returning the lubricating oil. There was a problem that the design became complicated.

However, according to the second aspect of the present invention, since the blower (14, 27) is the object of control, the control completed within the air conditioner is not restricted by the control conditions on the engine side. It becomes possible, and it is possible to respond easily and surely.

According to the third aspect of the present invention, each air conditioning unit (12, 25) has an inside air inlet (44, 47) for introducing the inside air of the vehicle and an outside air inlet (45) for introducing the outside air of the vehicle. , 48) and the inside air inlet (44, 47)
And an opening / closing means (46, 49) for opening / closing the outside air inlet (45, 48), and an inside air temperature detecting means (41) for detecting the inside air temperature (Tr) and an outside air temperature (T).
The second control means (S50A) for controlling the opening degree of each opening / closing means (46, 49) is provided in accordance with each detection signal from the outside air temperature detecting means (41) for detecting (am). The blower (27) is driven for a predetermined period (T
When operating for a predetermined time (Tn) in s), the second control means (S50A) controls the opening degree of the opening / closing means (49) so as to introduce the air having the higher temperature among the detection signals. It is characterized by doing so.

As a result, air of higher temperature can be blown to the evaporator (28), so that the heat load on the evaporator (28) is increased to increase the amount of refrigerant flowing and enhance the effect of lubricating oil return. be able to. Alternatively, the predetermined time (Tn) can be further shortened to obtain the effect of returning the lubricating oil in a short time.

Further, in the invention described in claim 4, when the fan used in each blower (14, 27) rotates in the direction opposite to the rotation direction during normal operation, the direction of air flow becomes opposite. The first control means (S
100A) is characterized in that the blower (27) is operated in the reverse rotation direction when it is operated.

As a result, the blast air is sent to the air conditioning unit (1
Since it is possible to prevent the air from being blown out from each of the outlets (38a, 39a) of (2, 25), it is possible to suppress the occupant from feeling uncomfortable due to the air applied as a heat load to the evaporator (15, 28). .

The reference numerals in parentheses of the above-mentioned means indicate the corresponding relationship with the concrete means described in the embodiments described later.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) FIGS. 1 to 4 show a first embodiment of the present invention. In the first embodiment, the refrigeration cycle apparatus R is applied to a dual air conditioner type vehicle air conditioner having a plurality of air conditioning units 12 and 25, and is installed in a minivan type passenger vehicle. In addition, this vehicle air conditioner is set to have an automatic air conditioner in which a movable part described below is automatically controlled.

FIG. 1 shows the overall construction of the vehicle when it is mounted. Minivan type vehicle 10 passenger compartment 11
The second and third seats (rear seats) are arranged behind the front seats (driver's seat and passenger seat) to form a long space in the vehicle front-rear direction. Reference numeral 11a denotes a floor surface of the passenger compartment 11.

The vehicle air conditioner includes a front seat side air conditioning unit 1
2 and a rear seat side air conditioning unit 25.

The front seat side air conditioning unit 12 is arranged inside a forefront instrument panel (not shown) in the vehicle compartment 11 and air-conditions an area on the front seat side of the vehicle compartment. The front seat side air conditioning unit 12 has a case 13 that forms an air passage, and a blower 14 is arranged at an upstream portion of the case 13. As shown in FIG. 2A, the blower 14 blows the inside air or the outside air switched and introduced by the inside / outside air switching door 46 that opens / closes the inside air inlet 44 and the outside air inlet 45.

An evaporator (main evaporator) 15 of the refrigeration cycle apparatus R is arranged downstream of the blower 14 as a cooling heat exchanger for cooling the blown air. Here, the refrigeration cycle apparatus R has a well-known configuration, and a vehicle engine (not shown)
1 driven by the electromagnetic clutch 16a
6 is provided. The gas-phase refrigerant is compressed to a high temperature and high pressure by the compressor 16, the gas-phase refrigerant discharged from the compressor 16 is introduced into the condenser 17, and the gas-phase refrigerant is blown by the cooling fan (not shown) in the condenser 17. Liquefied and condensed by exchanging heat with the outside air.

The refrigerant passing through the condenser 17 is separated into a liquid phase refrigerant and a vapor phase refrigerant by the liquid receiver 18, and the liquid phase refrigerant is stored in the liquid receiver 18. The liquid-phase refrigerant from the liquid receiver 18 is expanded to a low temperature and low pressure by a temperature type expansion valve 19 as an expansion valve, and the low temperature and low pressure refrigerant absorbs heat from the conditioned air and is evaporated in the evaporator 15. .

As is well known, the temperature type expansion valve 19 automatically adjusts the valve opening so that the degree of superheat of the refrigerant at the outlet of the evaporator 15 is maintained at a predetermined value. Therefore, the temperature-type expansion valve 19 includes a temperature sensing unit that senses the refrigerant temperature at the outlet of the evaporator 15, a first pressure chamber to which a pressure corresponding to the refrigerant temperature sensed by the temperature sensing unit is applied, and the evaporator 15. A second pressure chamber to which a refrigerant pressure (low cycle pressure) is applied and a diaphragm for partitioning the first and second pressure chambers are provided, and the diaphragm and the valve are arranged according to the pressure difference between the first and second pressure chambers and the spring force. The body is displaced to adjust the refrigerant flow rate. Specifically, for example, when the temperature of the temperature sensing part rises, the pressure of the first pressure chamber rises, and the valve body is displaced through the diaphragm in the opening direction to increase the refrigerant flow rate.

In the evaporator 15, the evaporated gas refrigerant is again sucked into the compressor 16 and compressed. In addition,
Of the refrigeration cycle device R, the compressor 16, the condenser 17,
Devices such as the liquid receiver 18 are mounted in the engine room 20 on the front side of the vehicle interior 11.

In the front seat side air conditioning unit 12,
A temperature sensor 21 is arranged at the air outlet of the evaporator 15, and when the evaporator outlet air temperature (evaporator cooling temperature) Te detected by the temperature sensor 21 falls below a predetermined value, the electromagnetic clutch 16a is energized. Shut off the compressor 1
By stopping the operation of No. 6, the frost of the evaporator 15 is prevented.

On the downstream side of the evaporator 15 in the air flow,
A heater core (heating heat exchanger) 22 for heating the conditioned air with hot water from the vehicle engine is arranged. A bypass 23 is formed on the side of the heater core 22. A plate-shaped air mix door 24 is rotatably arranged adjacent to the heater core 22, and the hot air heated by passing through the heater core 22 and the bypass passage 23 are selected by selecting the rotating position of the air mix door 24. The blown air temperature is adjusted by adjusting the air volume ratio with the cold air passing through.

Further, at the downstream end of the front seat side air conditioning unit 12, a defroster blow-out opening, a face blow-out opening and a foot blow-out opening (not shown) are opened, and these openings are opened by a blow-out mode door (not shown). The conditioned air that has been switched and opened / closed and passed through each opening is blown out toward the inner surface of the vehicle window glass, the head and foot of the front seat occupant, respectively.

Next, the rear seat side air conditioning unit 25 controls the rear portion of the passenger compartment 11, for example, to air-condition the rear seat side of the passenger compartment.
It is placed in the side part of the rear seat. As shown in FIG. 2B, an inside air introduction port 47 and an outside air introduction port 48 are provided on the upstream side of the case 26 of the rear seat side air conditioning unit 25, and the inside and outside air that opens and closes both the introduction ports 47, 48. A switching door (hereinafter referred to as a door) 49 is provided. Further, a rear seat side blower 27 is provided on the downstream side of the door 49, and blows inside air or outside air which is switched and introduced by opening and closing the door 49.

A rear seat evaporator (sub-evaporator) 28 is arranged downstream of the rear seat blower 27. A heater core (heating heat exchanger) 29 that heats the conditioned air with hot water from the vehicle engine is arranged downstream of the rear seat evaporator 28 in the air flow. A bypass passage 30 is formed on the side of the heater core 29. A plate-like cold air bypass door 31 is rotatably arranged adjacent to the heater core 29, and the cold air bypass door 31 opens and closes the bypass passage 30 in accordance with the blowing mode and the air volume level of the rear seat side air conditioning unit 25.

A rear seat side thermal expansion valve 32 as an expansion valve is provided at the refrigerant inlet portion of the rear seat evaporator 28. The rear seat side thermal expansion valve 32 is the front seat side thermal expansion valve 1
9 is the same as that of FIG. 9 and expands the high-temperature high-pressure liquid-phase refrigerant from the liquid receiver 18 into the low-temperature low-pressure refrigerant, and the superheat degree of the refrigerant at the outlet of the rear seat side evaporator 28 is set to a predetermined value. The flow rate of the refrigerant is adjusted by adjusting the valve opening so that the value becomes a value.

In the refrigeration cycle apparatus R, the inlet side of the rear seat side thermal expansion valve 32 is connected to the inlet side of the front seat side thermal expansion valve 19 via an underfloor high pressure pipe 33, and the rear seat The outlet side of the side evaporator 28 is connected to the outlet side of the evaporator 15 on the front seat side via an underfloor low pressure pipe 34. As a result, the rear seat side thermal expansion valve 32 and the rear seat evaporator 28 are connected in parallel with the front seat side thermal expansion valve 19 and the evaporator 15. Since the underfloor high-pressure pipe 33 and the underfloor low-pressure pipe 34 are arranged in the underfloor space 35 formed below the floor surface 11a of the vehicle compartment 11, the underfloor high-pressure pipe 33 and the underfloor low-pressure pipe 34 have a predetermined height L (for example, 600 mm) from the suction pipe 16b of the compressor 16. It is placed in the lower part.

In the rear seat side air conditioning unit 25, the face outlet opening 36 and the outlet mode door 37 are arranged immediately downstream of the rear seat evaporator 28.
The cool air cooled by the rear-seat evaporator 28 is blown from the face blow-out opening 36 through the rear-seat face duct 38 and from the ceiling outlet 38a toward the head of the rear-seat occupant.
The warm air heated by the heater core 29 passes through the rear-seat foot duct 39 and is blown from the rear-seat foot outlet 39a toward the feet of the rear-seat occupant.

FIG. 3 is a schematic block diagram of electric control of the automatic air conditioner according to this embodiment.
0 is composed of a microcomputer and its peripheral circuits. In addition to the evaporator outlet air temperature Te detected by the temperature sensor 21, an inside air temperature T detected from a sensor group 41 having an inside air sensor, an outside air sensor, a solar radiation sensor, and a water temperature sensor as temperature detecting means (not shown).
r, the outside air temperature Tam, the amount of solar radiation Ts, the hot water temperature Tw, etc. are input. Further, operation signals such as temperature setting in the passenger compartment, air volume adjustment, inside / outside air mode switching, blowout mode switching, and compressor ON-OFF are input from the front seat side operation panel 42. On the other hand, from the rear seat side operation panel 43, operation signals for rear seat side air volume adjustment, inside / outside air mode switching, blowing mode switching, etc. are input. The operation signals for adjusting the air volume on the rear seat side, switching the inside / outside air mode, and switching the blowout mode can be input from the front seat side operation panel 42.

The air-conditioning control device 40 performs predetermined arithmetic processing according to a preset program and outputs an output signal, and air-conditioning equipment on the front seat side and the rear seat side (the electromagnetic clutch 16).
a, blowers 14, 27, air mix doors 24, 31,
The operation of the drive motor group M) for the inside / outside air switching doors 46, 49 and the like is controlled.

In the present embodiment, the air conditioner control device 40 is utilized so that the rear seat side blower 2 is installed therein.
Rear seat side blower 27 at a predetermined cycle Ts when 7 is stopped
A timer circuit for operating Tn for a predetermined time and a program for controlling the timer circuit are provided. Specifically, the rear seat blower 27 is operated for a predetermined time Tn after measuring the predetermined time Tx, and the predetermined cycle T
s is defined as the sum of the predetermined time Tx and the predetermined time Tn. (Ts = Tx + Tn) Further, the inside air temperature T detected by the sensors of the sensor group 41.
A program for controlling the opening degree of the door 49 in the rear seat side air conditioning unit 25 is provided so as to compare r and the outside air temperature Tam and introduce the higher temperature air.

Next, the operation based on the above configuration will be described. First, when operating both the front seat side air conditioning unit 12 and the rear seat side air conditioning unit 25, both the front and rear air blowers 14, 27 are operated to operate both air conditioning units 12, 25.
Blow to. When the air conditioner switch (compressor operation switch) of the front seat side operation panel 42 is turned on, the electromagnetic clutch 16a is energized and brought into a connected state, so that the compressor 16 is driven by the vehicle engine.

In the front seat side air conditioning unit 12, after the inside air or the outside air is selected by the inside / outside air switching door 46, the blown air is cooled and dehumidified by the evaporator 15, and then reheated by the heater core 22. Further, the air mix door 24 is used to arbitrarily adjust the air flow rate ratio of the cool air and the warm air to adjust the temperature of air blown into the vehicle interior.

On the other hand, in the rear seat side air conditioning unit 25, after the inside air or the outside air is selected by the door 49, the blowout mode door 37 switches the blowout mode between the face mode and the foot mode, and in the face mode, the rear seat side evaporator. The cold air that has been cooled and dehumidified by 28 is blown to the rear seat side of the passenger compartment through the rear seat side face duct 38 through the rear seat side ceiling outlet 38a. Further, in the foot mode, the blown air passes through the rear-seat evaporator 28 and is heated by the heater core 29 to become warm air, which passes through the rear-seat foot duct 39 and the rear-seat foot outlet 39a to the occupant's feet. Blow out to.

By the way, both the front and rear air conditioning units 12,
When 25 is operated at the same time as described above, the front and rear temperature type expansion valves 19 and 32 are connected to the front and rear evaporators 15 and 2, respectively.
The valve opening degree corresponding to the heat load of No. 8 and the flow rate of the refrigerant corresponding to the heat load are always passed through the flow paths of the evaporators 15 and 28. Therefore, the underfloor low-pressure pipe of the rear seat side air conditioning unit 25 is provided. Lubricating oil for the compressor does not collect in 34 and the like.

However, when the occupant is on the front seat side only and the occupant is not on the rear seat side, the rear seat side is operated by operating the switch on the front seat side operation panel 42 or the rear seat side operation panel 43. The blower 27 is stopped. As a result, the conditioned air is not blown to the rear seat side air conditioning unit 25, and the air conditioning function of the rear seat side air conditioning unit 25 is stopped, so that only the front seat side air conditioning unit 12 is in the independent operation state.

During the front seat side independent operation, in the rear seat side air conditioning unit 25, the rear seat side temperature type expansion valve 32 repeats minute opening and closing operations, so that the lubricating oil in the liquid phase is dispersed in the rear seat side evaporator 28. It accumulates in the underfloor low-pressure pipe 34 on the outlet side of the rear-seat evaporator 28. In particular, the underfloor low pressure pipe 34 is
Since it is arranged at a position lower than the suction pipe 16b of the compressor 16 by a predetermined amount L (for example, about 600 mm),
The phenomenon of stagnation of lubricating oil in the underfloor low-pressure pipe 34 easily occurs.

In the dual air conditioner type vehicle air conditioner in which the solenoid valves for the evaporators 15 and 28 are eliminated for cost reduction, if the compressor 16 is continuously operated for a long time during the front seat side independent operation. The minute opening and closing of the rear-seat temperature expansion valve 32 is repeated for a long time, and the phenomenon of stagnation of lubricating oil in the underfloor low-pressure pipe 34 becomes significant, and there is a risk of insufficient lubricating oil returning to the compressor 16.

Therefore, in this embodiment, the underfloor low pressure pipe 3 is used.
In order to eliminate the stagnation phenomenon of the lubricating oil in No. 4, the control for forcibly operating the stopped rear seat blower 27 at a predetermined cycle Ts is adopted. In addition, in order to obtain the operation more effectively, a control for selecting the inside air or the outside air introduced into the rear seat side unit 25 according to the temperature condition is adopted.

FIG. 4 is a flow chart showing a control routine executed by a program previously provided in the air conditioning controller 40, and its control operation will be described below.

The control routine is started by turning on the auto switch or the air conditioner switch (compressor operation switch) on the front seat side operation panel 42. First, in step S5.
Then, the detection signals of the sensors 21, 41, the operation panels 42, 4
Read the operation signal from 3.

Next, in step S10, it is determined from the state of each signal in step S5 whether the blower 14 on the front seat side is in the operating state. If it is in operation, step S20
Then, it is determined whether the air conditioner is in the operating state. If it is in the operating state, it is further determined in step S30 whether the rear seat blower 27 is in the operating state. Here, no, that is, when the blower 14 and the evaporator 15 on the front seat side are mainly operated, and the blower 27 on the rear seat side (rear seat evaporator 28) is stopped,
In step S40, the timer for the rear seat blower 27 is started. If the result of step S10 or step S20 is negative, or if the rear-seat blower 27 is in operation in step S30, the process returns to step S5 and is repeatedly controlled.

Next, step S5 as the second control means.
At 0A, switching control between the inside and outside air is performed. That is, in step S50, the inside air temperature Tr detected by the sensor group 41,
The detection signals of the outside air temperature Tam are compared with each other, and the outside air temperature T
When am is high, it is determined in step S60 whether the door 49 opens the outside air introduction port 48.

If the outside air inlet port 48 is open, the process directly proceeds to the next step S100A. If not, the door 49 opens the outside air inlet port 48 in step S70 and the process proceeds to step S100A.

On the other hand, if it is determined in step S50 that the inside air temperature Tr is higher, it is determined in step S80 whether the door 49 opens the inside air introduction port 47.

If the inside air introducing port 47 is opened, the process proceeds to the next step S100A as it is. If not, the door 49 opens the inside air introducing port 47 in step S90 and the process proceeds to step S100A. (Here, step S50A of the second control means ends.) Then, in step S100A as the first control means,
The rear seat blower 27 is controlled to operate for a predetermined time Tn at a predetermined cycle Ts.

That is, it is determined in step S100 whether or not the measurement time T of the timer started in step S40 has exceeded a predetermined time Tx, and if so, in step S110, the rear seat blower 27 is determined. For a predetermined time Tn
I am trying to work only. Here, the rear seat blower 2
The setting voltage Vn applied to 7 should be set to a value between the starting voltage that can drive the rear seat blower 27 and the minimum setting voltage during normal operation so as not to give an occupant an uncomfortable feeling. ing. If it is determined to be no in step S100, the time measurement is continued until the measurement time T reaches the predetermined time Tx. (Here, step S100A of the first control means ends.) Then, after step S110, the timer is cleared in step S120.

The function and effect of the present embodiment will be described based on the above-mentioned configuration and operation description.

By providing the step S100A as the first control means, the heat load is applied to the stopped rear seat evaporator 28 by the air blown from the rear seat blower 27. Then, the rear seat side thermal expansion valve 32 is opened, the rear seat side evaporator 28 is activated, and the refrigerant is allowed to flow inside the rear seat side evaporator 28. Therefore, the lubricating oil for the compressor, which stays in the rear-seat evaporator 28, the underfloor low-pressure pipe 34 to the compressor 16 and the like during the stop, can be returned to the compressor 16 side.

Here, by utilizing the rear seat blower 27 in the refrigeration cycle device R and operating the rear seat blower 27, which is originally stopped, at the predetermined cycle Ts for a predetermined time Tn, the lubricating oil Since it can be returned, the reliability of the rear seat blower 27 is not reduced.

When applied to a vehicle air conditioner in the prior art, signals from both the air conditioner control device controlling the air conditioner and the engine controller controlling the engine operating condition are normally exchanged. Since the compressor 16 is often controlled, it is necessary to change both the air conditioning control device and the engine control device in order to newly control the compressor 16 for returning the lubricating oil. There was a problem that the design became complicated.

However, according to this embodiment, since the blowers 14 and 27 are to be controlled, the control which is completed in the air conditioner can be performed without being restricted by the control conditions on the engine side. You can respond reliably.

Further, step S50 serving as the second control means.
In A, the inside air temperature Tr and the outside air temperature Tam are compared, and the door 4
Since the opening degree of 9 is controlled, the air of higher temperature can be blown to the rear seat evaporator 28, and the rear seat evaporator 2
It is possible to increase the heat load on 8 to increase the amount of circulating refrigerant and enhance the effect of lubricating oil return. Alternatively, the predetermined time Tn can be further shortened to obtain the effect of returning the lubricating oil in a short time.

Although the rear seat side air conditioning unit 25 has been described as having the rear seat evaporator 28 and the heater core 29, the heater core 29 may be omitted and only the cooler function may be provided.

(Second Embodiment) When the fans used in the blowers 14 and 27 in the first embodiment are rotated in the direction opposite to the rotation direction during normal operation, such as an axial fan, Assuming that the air flow direction is opposite, in step S100A (step S110) as the first control means, the rear seat blower 27 may be operated in the reverse rotation direction when operating.

As a result, the blown air can be prevented from being blown out from the outlets 38a, 39a of the rear seat side air conditioning unit 25, so that the air given to the rear seat side evaporator 28 as a heat load is applied to the passenger. It is possible to suppress the discomfort.

(Other Embodiments) In the first embodiment, assuming that the front seat side air conditioning unit 12 mainly operates, the rear seat blower 27 and the door 49.
However, it is assumed that the rear seat side air conditioning unit 25 mainly operates (the front seat side blower 14 and the evaporator 1).
5 may be stopped), the blower 14 on the front seat side and the inside / outside air switching door 46 may be controlled.

Further, in the first embodiment described above, an automatic air conditioner is assumed, and the timer circuit, the first control means, and the second control means are incorporated by utilizing the air conditioning control device 40, but the invention is not limited to this. It may be compatible with the case of an air conditioner.

In the case of a manual air conditioner, the second control means (step S50A in FIG. 4) relating to the control of the inside / outside air switching doors 46, 49 is eliminated and the timer circuit and control for controlling the blowers 14, 27 are eliminated. Program (Step S100 as First Control Means
If A) is provided in the front seat side operation panel 42, for example,
Lubricating oil return control can be performed easily and reliably.

Further, the air conditioning unit, that is, the expansion valve, the evaporator, and the blower disposed inside are not limited to two positions on the front seat side and the rear seat side, but may be three or more. In this case, for example, in the flowchart shown in FIG. 4, after step 20, the same control as that after step 30 may be performed for each blower.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a vehicle mounted state in a first embodiment of the present invention.

FIG. 2 shows the inside / outside air switching door in FIG.
(A) is a front seat side, (b) is a rear seat side block diagram.

FIG. 3 is a block diagram showing an air conditioning control device.

FIG. 4 is a flowchart for controlling a rear seat blower and an inside / outside air switching door.

[Explanation of symbols]

R Refrigeration cycle device 12 Front seat air conditioning unit 14 blower 15 Evaporator 16 compressor 17 condenser 19 Temperature expansion valve (expansion valve) 25 Rear seat air conditioning unit 27 Rear seat blower (Blower) 28 Rear seat evaporator (evaporator) 32 Temperature expansion valve for rear seat (expansion valve) 41 sensor group (temperature detection means) 44, 47 Inside air inlet 45, 48 Outside air inlet 46, 49 Inside / outside air switching door (opening / closing means)

Claims (4)

[Claims] 1. A compressor (16) for compressing a vapor-phase refrigerant to a high temperature and high pressure, a condenser (17) for liquefying and condensing the compressed vapor phase refrigerant, and an expansion for expanding the liquefied and condensed refrigerant to a low temperature and low pressure. Valve (1
9 and 32) and evaporating the expanded refrigerant, and at the same time the compressor (1
The evaporator (15, 28) to be discharged to 6) is sequentially connected by a refrigerant pipe, and the expansion valve (19, 32) and the evaporator (15, 2)
8) are arranged in parallel in pairs while refrigerant flows from the condenser (17) toward the compressor (16), and the expansion valves (19, 32) are arranged in parallel with each other. Each evaporator (15,
28) is a temperature type expansion valve (19, 32) that opens and closes according to the degree of superheat of the outlet refrigerant, and the evaporators (15, 28) are blown with air to blow off the evaporators (15, 28). ) To operate the blower (1
In the refrigeration cycle device provided with the blower (27), the blower (27) corresponding to the evaporator (28) is rotated at a predetermined cycle ( A refrigeration cycle apparatus comprising: first control means (S100A) for operating for a predetermined time (Tn) at Ts). 2. A plurality of air-conditioning units (12, 25) for air-conditioning a vehicle interior, and the refrigeration cycle apparatus (R) according to claim 1, wherein each of the air-conditioning units (12, 25) includes: The expansion valves (19, 32) of the refrigeration cycle device (R),
The evaporator (15, 28), the blower (14, 27)
An air conditioner for a vehicle, characterized in that 3. The inside air inlets (44, 47) for introducing the inside air of the vehicle to the air conditioning units (12, 25), respectively.
And an outside air inlet (45, 48) for introducing the outside air of the vehicle,
Opening / closing means (46, 49) for opening / closing the inside air inlets (44, 47) and the outside air inlets (45, 48).
And an inside air temperature detecting means (41) for detecting the inside air temperature (Tr).
And second control means (S50) for controlling the opening degree of each of the opening / closing means (46, 49) according to each detection signal from the outside air temperature detecting means (41) for detecting the outside air temperature (Tam).
A) is provided, and the blower (27) is driven by the first control means (S100A) at the predetermined period (Ts) for the predetermined time (Ts).
n) When operating, the second control means (S50A)
The air conditioner for a vehicle according to claim 2, wherein the opening degree of the opening / closing means (49) is controlled so as to introduce the air having a higher temperature among the detection signals. . 4. The fan used in each of the blowers (14, 27) is such that when it rotates in a direction opposite to the direction of rotation during normal operation, the direction of air flow is opposite. The control means (S100A) uses the blower (2
The vehicle air conditioner according to claim 2 or 3, characterized in that, when 7) is operated, it is operated in a reverse rotation direction.