JP3276009B2 - Vehicle air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for a vehicle, and more particularly to an air conditioner for a vehicle capable of cooling and heating by integrally using a refrigerant compressor and a viscous fluid coupling.

[0002]

2. Description of the Related Art Conventional general cooling systems for vehicles include various types of refrigerant compressors such as a vane type, a rotary swash plate type and a scroll type compressor in which the driving force of an engine is transmitted through an electromagnetic clutch. Is connected to a refrigeration circuit. The drive shaft of the refrigerant compressor is driven when the electromagnetic clutch is turned on, thereby performing the compression work of the refrigerant gas through a change in the volume of the bore. The high-temperature, high-pressure compressed refrigerant discharged from this refrigerant compressor is liquefied by a condenser, expanded into a low-temperature, low-pressure mist by an expansion valve, and then cooled by ambient heat with an evaporator by latent heat. Thus, the air is cooled in the vehicle compartment, and then is sucked into the refrigerant compressor again.

[0003] As a conventional heating device for a vehicle, a heating device in which a viscous fluid coupling is connected to a cooling circuit of an engine is also known (Japanese Patent Laid-Open No. 3-57877). The viscous fluid coupling in the vehicle heating device includes a housing, an input shaft supported in the housing and transmitting the driving force of the engine via an electromagnetic clutch, and a labyrinth groove fixed to the input shaft in the housing. And a cover formed with a labyrinth groove fixed to the housing and fitted with a predetermined gap to the labyrinth groove of the rotor, and a viscous fluid such as silicone oil is sealed between the rotor and the cover. The circulating water sealed between the cover and the housing is circulated to the engine cooling device. In this viscous fluid coupling, when the rotor rotates due to the rotation of the input shaft, the viscous fluid sealed between the cover fixed to the housing generates heat due to shearing of the relative rotation between the rotor and the cover. The circulating water transmitted to the circulating water sealed between the cover and the housing and heated is used for heating the vehicle interior by the heater. The circulating water that has passed through the heater is used for cooling the engine together with the return circulating water from the radiator, and is circulated again from the engine to the radiator and the heater.

[0004]

However, if cooling or heating of the vehicle interior is performed using the above-mentioned conventional general vehicle cooling device and heating device, the refrigerant compressor and the viscous fluid coupling are respectively connected to each other. Due to the necessity of having separate electromagnetic clutches and connecting them by belts or the like, the mounting space in a limited-sized engine room is widened, and there is a problem in mountability. In this case, since the refrigerant compressor and the viscous fluid coupling each require separate electromagnetic clutches, problems of weight increase and cost increase arise.

An object of the present invention is to achieve heating and cooling while realizing excellent mountability, light weight and low cost.

[0006]

SUMMARY OF THE INVENTION The present invention provides a vehicle air conditioner having a refrigeration circuit including a refrigerant compressor, a condenser, an expansion valve, and an evaporator. An input shaft operatively connected to the engine, a viscous fluid coupling connecting the input shaft and the drive shaft of the refrigerant compressor via a viscous fluid, and a restraint for selectively restraining rotation of the drive shaft. Means and a heat exchange mechanism that functions by the thermal energy generated in the viscous fluid coupling based on the relative rotational movement between the restrained drive shaft and the input shaft. .

[0007] An electromagnetic clutch can be provided between the engine and the input shaft. The heat exchange mechanism can be equipped with a temperature detecting means.

[0008]

In the vehicle air conditioner of the present invention, when the drive shaft of the refrigerant compressor is in the released state, the rotation of the input shaft is caused by the rotation of the input shaft by the engine, whereby the rotation of the input shaft is caused by the viscous fluid in the viscous fluid coupling. As a result, torque is transmitted to the drive shaft, and the drive shaft also rotates. For this reason, the refrigerant compressor performs compression work and circulates the compressed refrigerant through the refrigeration circuit, thereby cooling the passenger compartment.
At this time, since the relative rotation between the input shaft and the drive shaft hardly occurs in the viscous fluid coupling, the viscous fluid does not generate heat energy and does not exchange heat with the heat exchange mechanism. Not done.

Further, when the drive shaft of the refrigerant compressor is in the locked state, the rotation of the input shaft is not transmitted to the drive shaft even if the input shaft is rotated by the engine. Therefore, the viscous fluid coupling causes relative rotation between the input shaft and the drive shaft, and heat energy is generated by shearing of the viscous fluid. The generated heat is used to exchange heat with the heat exchange mechanism, thereby heating the passenger compartment. At this time, since the drive shaft does not rotate, the refrigerant compressor does not perform compression work and does not circulate the compressed refrigerant to the refrigeration circuit, so that the vehicle compartment is not cooled.

In this way, in this vehicle air conditioner, even if at least one electromagnetic clutch is omitted, the refrigerant compressor and the heat exchange mechanism are selectively operated by selecting the engagement and release of the drive shaft, Cooling or heating of the vehicle interior can be performed. For this reason, the installation space in the limited engine room can be reduced. When the input shaft is directly connected to the engine, the engagement or release of the drive shaft causes heating or cooling while the engine is rotating. In the vehicle air conditioner of the present invention, when an electromagnetic clutch is provided between the engine and the input shaft, cooling and heating can be turned ON / OFF even while the engine is rotating. . For example, during operation of the vehicle, if neither cooling nor heating is desired, the electromagnetic clutch is turned off. If cooling is desired during operation of the vehicle, the electromagnetic clutch is turned on and the drive shaft is released. If heating is desired during operation of the vehicle, the electromagnetic clutch is turned on and the drive shaft is locked.

Further, in the air conditioner for a vehicle according to the present invention, the load fluctuation generated on the input shaft at the time of starting the refrigerant compressor or the like is absorbed by the viscous fluid of the viscous fluid coupling, so that the torque fluctuation of the engine is reduced. It has no severe effect on the refrigerant compressor. In the vehicle air conditioner of the present invention,
When the heat exchange mechanism is provided with temperature detecting means, it can be detected by the viscous fluid coupling that thermal energy of the viscous fluid is being generated. Therefore, for example, if the refrigerant compressor is locked due to seizure during the release of the drive shaft, it is possible to know the abnormality of the vehicle air conditioner by detecting the heat energy generation of the viscous fluid by the temperature detecting means. For example, an operation such as turning off the electromagnetic clutch can be performed.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. In this vehicle air conditioner, as shown in FIG. 1, an electromagnetic clutch 1, a viscous fluid coupling 2 provided integrally with the electromagnetic clutch 1, and a swash plate type provided integrally with the viscous fluid coupling 2. The compressor 3 is included.

In the electromagnetic clutch 1, a clutch rotor 20 connected to a rotor 4a of an engine 4 (see FIG. 2) by a belt (not shown) is supported on the outer periphery of a boss 21a extending from a front housing 21 via a bearing 21b. The input shaft 22 is supported on the inner periphery of the boss 21a via a bearing 21c. A solenoid 24 is fixed to the outer periphery of the boss 21a, and the solenoid 2
Numeral 4 is excitable by a control signal from the CPU 5 (see FIG. 2). The input shaft 22 is provided with a disk-shaped armature 23. The armature 23 is attracted to the rotor 20 by the excitation of the solenoid 24, so that the input shaft 22 can be driven.

In the viscous fluid coupling 2, in the front housing 21, one cover 25 is fixed to the rear end of the input shaft 22 at a position deeper than the shaft sealing device 21d provided on the inner periphery of the boss portion 21a. The other cover 27 is fixed via a shaft sealing device 26a at the front end and a little behind the drive shaft 26 whose end faces each other with the shaft 22, and the two covers 25 and 27 are fixed by bolts. Labyrinth grooves 25a, 27 extending in the axial direction opposite to each other are formed in the covers 25, 27, respectively.
a is formed. A rotor 28 is fixed to a front end of a drive shaft 26 located inside each of the covers 25 and 27, and a labyrinth groove 28a extending in the axial direction is provided on the rotor 28 so as to be separated from each other. The labyrinth grooves 25a and 27a are fitted with a predetermined gap. Silicon oil as a viscous fluid is sealed between the rotor 28 and the covers 25 and 27.

Each cover 2 is provided in the front housing 21.
5 and 27, a heat exchange chamber A as a heat exchange mechanism is defined and an inlet 21e and an outlet 21f are formed in the front housing 21.
As shown in FIG. 2, 1e is connected to a cooling pipe which communicates with a water jacket of the engine 4 through an on-off valve 6, and an outlet 21f communicates with a heater 7 provided as a heat exchange mechanism provided in the vehicle interior. Connected to the cooling pipeline. The on-off valve 6 can be opened and closed by a control signal from the CPU 5. Further, the front housing 21 is equipped with a temperature sensor 45 as temperature detecting means, and the temperature sensor 45 is connected to the CPU 5 shown in FIG. The water jacket of the engine 4 is also connected to the radiator 8 by another cooling pipe, and the radiator 8 can be cooled by a cooling fan 9.

In the swash plate type compressor 3, as shown in FIG.
A center housing 34 is fixed to the front housing 21, and a pair of cylinder blocks 29, 30 is provided at the rear end of the center housing 34 via a valve plate 32. The cylinder blocks 29 and 30 form a swash plate chamber 31 at a connection portion, and a rear housing 35 is closed at a rear end thereof via a valve plate 33. Center housing 34
The rear housing 35 has an intake chamber 36 on the inner peripheral side.
Are formed, and a discharge chamber 37 is formed on the outer peripheral side. As shown in FIG. 2, the swash plate chamber 31 is connected to a refrigerant pipe communicating with the evaporator 10 provided in the vehicle interior. The front-side discharge chamber 37 and the rear-side discharge chamber 37 communicate with each other via a discharge passage (not shown), and the rear-side discharge chamber 37 is connected to a refrigerant pipe communicating with the condenser 11. The condenser 11 can be cooled by a cooling fan 12, and is connected again to the evaporator 10 via an expansion valve 14 by a refrigerant pipe.

The common shaft hole of each of the cylinder blocks 29, 30 has a drive shaft 2 through radial bearings 26b, 26c.
The drive shaft 26 penetrates through the valve plate 32 and is supported by the center housing 34 via a shaft sealing device 26d. A notch 41 is formed at the rear end of the drive shaft 26, and the notch 41 is formed in the rear housing 3.
A stopper 43 serving as a restraining means extending by excitation of a solenoid 42 provided in the inside 5 can be engaged against a biasing force of a spring 43a. Further, a swash plate 38 is fixed to the drive shaft 26 so as to be rotatable in the swash plate chamber 31.
The swash plate 38 is supported by the cylinder blocks 29, 30 via thrust bearings 29a, 30a. Also,
Each of the cylinder blocks 29 and 30 is formed with a plurality of pairs of front and rear bores 39 arranged in parallel around the drive shaft 26, and each bore 39 is a double-headed type moored to a swash plate 38 via a pair of shoes 40. A piston 41 is fitted so as to move linearly.

Each of the valve plates 32 and 33 is formed with a suction port communicating with a suction chamber 36 through a suction valve (not shown) between the bore 39 and each of the bores 39. A discharge port communicating with the discharge chamber 37 via a discharge valve (not shown) whose opening degree is limited is formed in a retainer (not shown). And, each cylinder block 29, 30
Includes a swash plate chamber 31, front and rear housings 34,
A plurality of suction passages 44 are formed so as to communicate with the respective suction chambers 35.

The heater 7 and the evaporator 10 can be blown by a fan 13. In this vehicle air conditioner, the CPU 5 closes the on-off valve 6, rotates the fan 13 and excites the solenoid 24 of the electromagnetic clutch 1 during the operation of the vehicle by the occupant's "cooling desired" operation, so that the swash plate compression is performed. The excitation of the solenoid 42 of the machine 3 is released. As a result, the stopper 43 is stored by the urging force of the spring 43a, and the engagement with the notch of the drive shaft 26 is released, so that the drive shaft 26 is released. Thus, the input shaft 22 is rotated from the engine 4 via the rotor 20 and the armature 23. Therefore, the covers 25 and 27 of the viscous fluid coupling 2 rotate together with the input shaft 22, and the labyrinth grooves 25a and
The rotor 28 rotates due to the viscosity of the silicone oil between the groove 27a and the labyrinth groove 28a. Therefore, torque is transmitted to the drive shaft 26, and the drive shaft 26 also rotates.

Therefore, in the swash plate type compressor 3, the return refrigerant is introduced from the evaporator 10 into the swash plate chamber 31, and the swash plate chamber 3
The return refrigerant in 1 is guided to the front and rear suction chambers 36 through the respective suction passages 44. Then, the rotation of the drive shaft 26 causes the respective pistons 41 to move directly in the respective bores 39 via the swash plate 38, so that the return refrigerant in the respective suction chambers 36 becomes the valve plate 32,
The air is sucked into each of the bores 39 whose volume is expanding through 33 suction ports. Thereafter, the compressed refrigerant is discharged from the respective bores 39 whose volume is being reduced to the front and rear discharge chambers 37 through the discharge ports of the valve plates 32 and 33, respectively. The compressed refrigerant in the front-side discharge chamber 37 is collected in the rear-side discharge chamber 37 via the discharge passage, and the compressed refrigerant is discharged to the condenser 11 and circulated to the evaporator 10. At this time, the fan 13 is rotating, and the evaporator 10 cools the surrounding air by the latent heat to cool the vehicle interior.

During this time, in the viscous fluid coupling 2, since the relative rotation between the input shaft 22 and the drive shaft 26 hardly occurs due to the viscosity of the silicon oil between the labyrinth grooves 25a, 27a and the labyrinth groove 28a, 25,
27 and the rotor 28 rotate almost synchronously,
The silicon oil does not generate heat and does not exchange heat with the circulating water between the covers 25 and 27 and the front housing 21. Therefore, heating of the vehicle compartment is not performed. At this time, the engine 4 is cooled by the circulating water via the radiator 8.

Also, during operation of the vehicle, the occupant "desired heating"
Operation causes the CPU 5 to open the on-off valve 6, and the fan 13
Is rotated, and the solenoid 24 of the electromagnetic clutch 1 is excited, and the solenoid 42 of the swash plate type compressor 3 is excited. As a result, the stopper 43 extends against the urging force of the spring 43a and engages with the notch of the drive shaft 26, so that the drive shaft 2
6 is in detention. As a result, the input shaft 22 is rotated from the engine 4 via the rotor 20 and the like, but the drive shaft 2 is rotated.
6 cannot be rotated. Therefore, in the viscous fluid coupling 2, the input shaft 22 and the drive shaft 26 rotate relative to each other, and the silicon oil between the labyrinth grooves 25a, 27a and the labyrinth groove 28a generates heat by shearing. Therefore, heat is exchanged with the circulating water in the heat exchange chamber A, and the heated circulating water is led out to the heater 7. At this time, since the fan 13 is rotating, the vehicle interior is heated by the heater 7. At this time, the engine 4 is also cooled by the circulating water through the radiator 8.

During this time, since the drive shaft 26 does not rotate,
Since the refrigerant compressor 3 does not perform the compression work and does not circulate the compressed refrigerant to the condenser 11, the cooling of the vehicle compartment is not performed.
Further, if the occupant does not perform the operation of “desired cooling / heating” during operation of the vehicle, the CPU 5 closes the on-off valve 6 and the fan 1
Then, the rotation of the solenoid 3 is stopped, the excitation of the solenoid 24 of the electromagnetic clutch 1 is released, and the excitation of the solenoid 42 of the swash plate type compressor 3 is released. As a result, no driving force is transmitted from the engine 4 to the input shaft 22. Therefore, neither cooling nor heating of the passenger compartment is performed. At this time, the engine 4 is also cooled by the circulating water through the radiator 8.

Thus, in this vehicle air conditioner, even if one electromagnetic clutch is omitted, the refrigerant compressor 3 and the heat exchange mechanism are selectively operated by switching the drive shaft 26 between the locked state and the released state. In addition, cooling or heating of the vehicle interior can be performed. For this reason, it is possible to reduce the mounting space in a limited-sized engine room.

Further, in this vehicle air conditioner, when the engine 4 is started with the electromagnetic clutch 1 turned on by the occupant's "cooling desired" or "heating desired" operation, the refrigerant compressor 3 is operated for a long time. If liquid compression occurs in the bore 39 when the drive shaft 26 is used again by releasing the drive shaft 26 from the unused state, the starting load of the engine 4 is changed to the viscous fluid coupling 2.
Absorbed by silicone oil. For this reason, the starting of the engine 4 is easy, and excellent driving feeling of the vehicle can be realized, and the electromagnetic clutch 1 and the refrigerant compressor 3 are not overworked.

Further, in this vehicle air conditioner, when the drive shaft 26 is released due to the operation of "desired cooling" or the non-operation of "desired cooling / heating" by the occupant, for example,
Even if the refrigerant compressor 3 is locked by seizure, it is possible to know the abnormality of the vehicle air conditioner by detecting the heat generation of the silicon oil by the temperature sensor 45. This allows
The occupant can turn off the electromagnetic clutch 1, for example.

In the above embodiment, the heat exchange mechanism is configured to also cool the engine. However, the heat exchange mechanism may be configured to heat only the vehicle compartment, and the compressor is not particularly limited to the swash plate type.

[0028]

As described in detail above, in the vehicle air conditioner of the present invention, since the refrigerant compressor and the viscous fluid coupling are integrally used, even if at least one electromagnetic clutch is omitted, the heating is not performed. And cooling can be enabled. Therefore, in this vehicle air conditioner, excellent mountability can be obtained by creating a superior vehicle interior environment and narrowing the installation space in a limited-sized engine room, and at the same time, achieving light weight and low weight. Cost can be realized.

Further, in this vehicle air conditioner, when an electromagnetic clutch is provided between the engine and the input shaft, cooling and heating are turned ON / OFF even while the engine is rotating. be able to. Furthermore, in this vehicle air conditioner, since the starting load of the engine is reduced,
An excellent driving feeling of the vehicle can be realized, and the life of the electromagnetic clutch and the refrigerant compressor can be extended.

In addition, in this vehicle air conditioner, when the heat exchange mechanism is provided with a temperature detecting means, it is possible to detect that the viscous fluid is generating heat, so that an abnormality of the vehicle air conditioner can be detected. You can know.

[Brief description of the drawings]

FIG. 1 is an integrated longitudinal sectional view of an electromagnetic clutch, a viscous fluid coupling, and a refrigerant compressor in a vehicle air conditioner of an embodiment.

FIG. 2 is a plan view of the vehicle air conditioner of the embodiment.

[Explanation of symbols]

4 Engine 22 Input shaft 2
... viscous fluid coupling 26 ... drive shaft 3 ... refrigerant compressor 43 ... stopper (locking means) 7 ... heater 8 ... radiator 11 ... condenser 1
0 ... Evaporator 14 ... Expansion valve 6 ... On-off valve 1
... Electromagnetic clutch 45 ... Temperature sensor (temperature detection means) A ... Heat exchange chamber

Continuation of the front page (56) References JP-A-3-98107 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) B60H 1/03 B60H 1/32 613

Claims (3)

(57) [Claims] An air conditioner for a vehicle having a refrigeration circuit comprising a refrigerant compressor, a condenser, an expansion valve and an evaporator, comprising: an input shaft interlocked with an engine; A viscous fluid coupling that couples the drive shaft via a viscous fluid, and a restraining unit that selectively restrains rotation of the drive shaft,
An air conditioner for a vehicle, comprising: a heat exchange mechanism that functions based on thermal energy generated in the viscous fluid coupling based on the relative rotational movement of the restrained drive shaft and the input shaft. 2. An air conditioner for a vehicle according to claim 1, wherein an electromagnetic clutch is provided between said engine and said input shaft. 3. A vehicle air conditioner according to claim 1, wherein said heat exchange mechanism is provided with a temperature detecting means.