KR20020089133A - Compressor for vehicle air-conditioning and air-conditioning apparatus with the compressor for vehicle air-conditioning - Google Patents

Abstract

PURPOSE: To provide a vehicular air conditioning technique effective in minimizing deterioration of electrical insulation in a vehicular air conditioning circuit. CONSTITUTION: In the air conditioner 100 for an automobile, the scroll type compressor 1 is attached directly to an engine E. A high pressure hose 106 and a low pressure hose 108 formed by a rubber material are provided in discharge piping 105 and suction piping 107. The scroll type compressor 1 compresses fluid of HFC based refrigerant mixed with PVE based refrigerating machine oil. The PVE based refrigerating machine oil has a function of maintaining lubricity of the refrigerant and also a function of minimizing deterioration of insulation resistance. Accordingly, even when moisture brought into the air conditioning circuit via the rubber material made high pressure hose 106 or low pressure hose 108 contacts an electrical connection part of an electric motor 49, deterioration of the insulation resistance is minimized and a leak in the electrical connection part is avoided.

Description

Compressor for Vehicle Air Conditioning and Air Conditioning Equipment with the Compressor for Vehicle Air Conditioning

The present invention relates to a vehicle air conditioning technology for performing air conditioning by compressing a fluid in which a refrigerant oil is mixed with a refrigerant in a vehicle by an air conditioning compressor to increase the pressure, and discharge the same into an air conditioning circuit.

Japanese Patent Laid-Open No. 10-338891 discloses a general air conditioner used for a room air conditioner and the like. This air conditioner compresses the refrigerant, increases the pressure, discharges the refrigerant into the air conditioning circuit, circulates the refrigerant through the air conditioning circuit, and performs air conditioning. In order to maintain the lubricity of the refrigerant, polyvinyl ether (hereinafter referred to as "PVE") Is mixed.

By the way, in the air conditioner described in the above publication, the refrigeration oil (PVE) for maintaining the lubricity of the refrigerant serves to absorb moisture in the air conditioning circuit. That is, since this refrigerator oil (PVE) has a lubrication function and a drying function, it is used for both the maintenance of lubricity of a refrigerant | coolant, and moisture absorption. As a result, the lubricity of the refrigerant can be maintained, and water in the system can be removed without using a dedicated desiccant, which is effective for solving the problem of atomization and clogging in the system.

However, the above publication merely proposes a technique of absorbing moisture introduced into the air conditioning circuit by the refrigeration oil, and does not propose an in-depth description of the electrical insulation effect of water in the air conditioning circuit. When moisture is mixed into the air conditioning circuit, electrical insulation is generally lowered, and therefore, a problem arises in that a short circuit is likely to occur at a conductive portion, for example, an electrical connection portion of an electric motor. And such a problem is especially concerned in the air conditioning circuit of the vehicle which is easy to receive moisture in the air conditioning circuit because it is used outdoors.

Accordingly, the inventors have found that in the vehicle air conditioner, in order to maintain the lubricity of the refrigerant, the refrigerant oil mixed with the refrigerant is also effective for ensuring electrical insulation. ) Was carefully reviewed. As a result, the present inventors can solve the problem of electrical insulation in the air conditioning circuit while maintaining the lubricity of the refrigerant, which is originally considered necessary, by using the PVE refrigerant oil mainly containing PVE in the vehicle air conditioner. Succeeded in finding out.

SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle air conditioning technology effective for suppressing a decrease in electrical insulation in an air conditioning circuit of a vehicle as much as possible.

1 is a view showing a state in which the air conditioner 100 of the present embodiment is attached to a vehicle body of an automobile.

2 is a longitudinal sectional view showing the entirety of the scroll compressor 1 of the present embodiment.

3 is a graph showing a correlation between moisture concentration and insulation resistance in PVE.

※ Explanation of code for main part of drawing ※

1: Scroll type compressor (vehicle air conditioning compressor) 2: Fixed scroll

6: motor housing 20: movable scroll

21: compression mechanism 32: compression chamber

45: motor room 46: stator

46a: stator coil 47: by contact

47a: space 47b: communication hole

49: electric motor 66: conductive pin

67, 68: conducting wire 100: air conditioning apparatus

102 condenser 103 receiver

104: cooling unit 106: high pressure hose

108: low pressure hose E: engine (vehicle engine)

In order to solve the said subject, the vehicle air conditioning compressor of this invention is comprised as described in Claims 1-4. The air conditioner of the present invention is configured as described in claim 5. In addition, the present invention can suppress the electrical insulation deterioration by moisture entering the air conditioning circuit by using a fluid in which a refrigerant oil containing polyvinyl ether oil (PVE) is mixed with a refrigerant in a vehicle air conditioning circuit. One technique to help. Therefore, the technique described in the present invention is not limited to simply applying polyvinyl ether oil (PVE) to refrigeration oil mixed in a refrigerant, but refrigeration oil containing polyvinyl ether oil (PVE) as a main component suppresses the deterioration of electrical insulation. The present invention was found to be effective in preventing the leakage of electric power, which is particularly concerned with the conductive parts of electric motors in an air conditioning circuit of a vehicle.

In the vehicle air conditioner compressor according to claim 1, a fluid obtained by mixing a refrigerant in which a refrigerant oil mainly containing polyvinyl ether oil (hereinafter referred to as "PVE") as a main component is compressed. As the "refrigerant" herein, a hydrofluorocarbon, for example, having R-134a as a main component (hereinafter referred to as "HFC type refrigerant") can be preferably used. The fluid compressed by the compressor and pressurized is discharged to the air conditioning circuit of the vehicle.

In addition, the conductive portion communicates with a flow path from suction to discharge of the fluid in which the refrigerant oil is mixed with the refrigerant. In other words, the fluid is in contact with the conductive portion. This "conductive part" shall include a wiring electrically connected, for example, the electrical connection part of an electric motor or other electric equipment widely. Therefore, when water is mixed in the flow path and the electrical insulation of the conductive portion is lowered, a short circuit is likely to occur. In addition, the conductive portion only needs to communicate with the flow path, and not only the case where the conductive part is arranged at a position branched from the flow path. The conductive portion may be disposed in the communication path itself.

The inventors of the present invention have focused on PVE, which is particularly effective in securing electrical insulation, among refrigeration oils in a vehicle air conditioner, and carefully examined the effect of moisture concentration in the PVE on electrical insulation (insulation resistance). As a result, the inventors of the present invention confirmed that the PVE-based refrigeration oil not only contributes to maintaining the lubricity of the refrigerant but also has high electrical insulation (insulation resistance) in the vehicle air conditioner. For example, a result has been obtained in which the insulation resistance of PVE is higher than that of ester refrigerator oil, which is generally used as a refrigerator oil for maintaining lubricity of refrigerant. As a result, the electrical insulation of the PVE itself is maintained, so that a short circuit can be avoided even if water is mixed in the flow path including the conductive portion as long as the conductive portion is in the atmosphere of the PVE system refrigeration oil.

As mentioned above, according to the vehicle air conditioner compressor of Claim 1, the fall of the electrical insulation in the air conditioning circuit of a vehicle can be suppressed as much as possible, and it can avoid that a short circuit generate | occur | produces an electroconductive part by the moisture which entered the air conditioning circuit.

In addition, the term "vehicle" as used in the present invention is intended to include various vehicles such as trams and trains in addition to automobiles.

In the vehicle air conditioning compressor according to claim 2, a compression mechanism for compressing a fluid obtained by mixing refrigerant oil with a refrigerant is connected to an electric motor. That is, this vehicle air conditioning compressor is electric. Therefore, by activating the electric motor which is the driving source of the compression mechanism, the sucked refrigerant is compressed through the compression mechanism together with the refrigeration oil, and the pressure is increased and discharged to the air conditioning circuit. Examples of the compression mechanism include a scroll type compressor that rotates the movable scroll with respect to the fixed scroll and performs a compression operation, or a reciprocating compression mechanism that performs the compression operation by reciprocating the piston in the cylinder bore.

Moreover, the electric connection part (conduction part) of an electric motor is made to communicate with a distribution path. That is, the fluid mixed with the refrigerant oil in the refrigerant comes into contact with the electrical connection of the electric motor. This "electrical connection part" electrically connects an electric motor with an external power supply, for example, conducting wire, a connection pin, etc. In this case, since the electrical insulation of the PVE itself is maintained, the short circuit can be avoided even if water is mixed in the flow path including the electrical connection portion as long as the electrical connection portion is in the PVE atmosphere.

Therefore, according to the vehicle air conditioner compressor according to claim 2, it is possible to avoid the occurrence of a short circuit in the electrical connection portion of the electric motor due to moisture entering the air conditioning circuit of the vehicle.

Here, it is preferable that the electric motor of Claim 2 is accommodated in the sealed motor chamber as described in Claim 3, and this motor chamber is a structure which communicates with a distribution path via a communication path. In this way, a part of the refrigerant and the refrigeration oil that flows through the distribution path is in a so-called "static" state in the motor compartment. In addition, if there is a pressure difference between the flow path side and the motor chamber side, the coolant flows so that the pressure between both flows equally. Therefore, heat transfer occurs between the coolant on the flow path side and the coolant inside the motor chamber, thereby causing electric The motor is cooled by the refrigerant. At this time, the refrigerant involved in the cooling of the electric motor is a part of the refrigerant moving along the distribution path, and it does not reach a significant increase in the temperature of the entire suction refrigerant. For this reason, the increase in the specific volume of a suction refrigerant is suppressed and there is little influence on the compression operation of an air conditioning compressor.

Thus, according to the vehicle air conditioner compressor of Claim 3, the same effect as the vehicle air conditioner compressor of Claim 2 can be exhibited, and cooling of an electric motor using a refrigerant | coolant can be performed reasonably.

In the vehicle air conditioning compressor according to claim 4, the compressor itself is attached to a vehicle engine which is a driving source of the vehicle. In addition, a circulation path through which a fluid in which a refrigerant is mixed with a refrigerant oil containing polyvinyl ether oil as a main component is connected to a pipe formed by using a rubber material. That is, the circulation path is connected to the piping in which the rubber material is used for the one part or all part. The pipe in which the rubber material is used may be a low pressure pipe connected to the suction side of the flow path, a high pressure pipe connected to the discharge side of the flow path, or both thereof. The pipe in which the rubber material is used may be a pipe on the air conditioning circuit side or a pipe on the compressor side.

When the vehicle air conditioning compressor is directly mounted on a vehicle engine that is a source of vibration or noise, it is a problem that the vibration or noise is transmitted to the compressor and affects other members. Rubber materials are generally used. In this case, since a pipe using a rubber material is used, a part of the moisture in the outside air passes through the pipe of the rubber material and enters the air conditioning circuit. Moreover, as long as a rubber material is used for the pipe, there is a limit to completely suppress the permeation of water in the pipe.

In the present invention, since the conductive part such as the electric connection part of the electric motor is configured to be in the PVE atmosphere, even if moisture in the outside air enters the air conditioning circuit through the piping of the rubber material, the occurrence of a short circuit in the conductive part can be avoided as much as possible. .

As described above, the vehicle air conditioner compressor of claim 4 is particularly effective for a vehicle air conditioner compressor of a type directly mounted on a vehicle engine in which moisture in the outside air is likely to enter the air conditioning circuit.

In the air conditioner of Claim 5, the fluid which mixed the refrigerant | coolant oil which has a polyvinyl ether oil as a main component with a refrigerant | coolant is sent to the air conditioning circuit of a vehicle through a vehicle air conditioning compressor, and air-conditioning is performed by circulating this air conditioning circuit. .

Therefore, according to the air conditioner of Claim 5, even if it has a conductive part in the distribution path | route of a vehicle air conditioning compressor, even if it has a conductive part in apparatuses other than this compressor, the fall of the electrical insulation in an air conditioning circuit is suppressed as much as possible. For example, it is possible to avoid the occurrence of a short circuit in the conductive portion due to moisture entering the air conditioning circuit.

Embodiment of the invention

EMBODIMENT OF THE INVENTION Below, one Embodiment of this invention is described based on drawing. In addition, the present embodiment applies the present invention to a scroll compressor that compresses, discharges and discharges a fluid in a compression chamber between a fixed scroll and a movable scroll. Here, FIG. 1: is a figure which shows the state in which the air conditioner 100 of this embodiment was attached to the vehicle body of an automobile. 2 is a longitudinal sectional view showing the entirety of the scroll compressor 1 of the present embodiment. 3 is a graph showing a correlation between moisture concentration and insulation resistance in PVE.

As shown in FIG. 1, the air conditioning apparatus 100 which performs air conditioning of an automobile is arrange | positioned in the engine room of a vehicle body. The air conditioner (100) is a scroll compressor (1) as a vehicle air conditioning compressor in the present invention, a condenser (102) as a condenser, a receiver (103), a cooling unit (104) equipped with an expansion valve and an evaporator, and these are connected to each other. Piping and the like are installed. That is, the high temperature and high pressure refrigerant which is adiabatically compressed and high-pressured by this scroll compressor 1 is sent to the condenser 102 and then to the receiver 103 through the discharge pipe 105. The liquid refrigerant liquefied in the condenser (102) and the receiver (103) is throttled and expanded by the expansion valve of the cooling unit (104) to form a throttle steam refrigerant, and then heat exchanges between the air conditioner and the air conditioner in the evaporator. To cool. The throttling steam refrigerant itself takes heat from the air-conditioning air and becomes a saturated vapor refrigerant evaporated under isostatic pressure, is sent to the scroll compressor (1) through the suction pipe (107), and is compressed again by the scroll compressor (1). . Thus, the air conditioning circuit is formed by the circuit which the refrigerant | coolant circulates around the scroll compressor 1, each apparatus connected to the circuit, etc.

In this embodiment, a mixture of an HFC refrigerant having R-134a (hydrofluorocarbon) as a main component and a refrigeration oil having a polyvinyl ether oil (PVE) as a main component is used. Therefore, the scroll compressor 1 compresses the fluid (hereinafter, referred to as "fluid") in which the PVE-based refrigerant oil is mixed with the HFC refrigerant, pressurizes it, and discharges it to the air conditioning circuit. This PVE refrigerant oil has good compatibility with the HFC refrigerant, and has the function of the original refrigerant oil with respect to the HFC refrigerant, that is, the lubricity of the HFC refrigerant.

The scroll compressor 1 is mounted directly on the engine E (corresponding to the vehicle engine in the present invention) as the compressor itself. The engine E is mechanically connected to an alternator (not shown), and the electric power generated by the alternator is transmitted to the electric motor 49 of the scroll compressor 1 via an inverter 60 to be described later. .

In addition, the discharge pipe 105 is provided with a high pressure hose 106 formed of a rubber material in addition to the high pressure pipe formed of a metal material. In addition, the suction pipe 107 is provided with a low pressure hose 108 formed by using a rubber material in addition to a low pressure pipe formed of a metal material. This is to avoid as much as possible that vibration or noise generated in the engine E affects other members through the scroll compressor 1 mounted directly on the engine E. As such, it is common to use pipes made of rubber material instead of metal pipes for piping where vibration or noise is a problem. However, when a pipe using a rubber material is used, it is known that a part of the moisture in the outside air passes through the pipe of the rubber material and enters the air conditioning circuit. In particular, in the air conditioner 100 for automobiles used outdoors, as long as a rubber material is used for the pipe, there is a limit to completely suppress the permeation of water in the pipe.

As shown in FIG. 2, one end surface of the center housing 4 is joined to one end surface of the fixed scroll 2 in the scroll compressor 1, and the motor housing 6 is connected to the other end surface of the center housing 4. Is joined. Therefore, the compressor main body is comprised by these housings 4 and 6 and the fixed scroll 2. The drive shaft 8 is rotatably supported by the center housing 4 and the motor housing 6 via the radial bearings 10, 12, and the drive shaft 8 is provided on the center of the center housing 4 side of the drive shaft 8. The eccentric shaft 14 which is eccentric with respect to is formed integrally.

The eccentric shaft 14 is fitted so that the bush 16 rotates integrally. A counterweight 18 is mounted at one end of the bush 16 so as to rotate integrally, and at the other end of the bush 16, the movable scroll 20 is opposed through the needle bearing 22 so that the movable scroll 20 faces the fixed scroll 2. It is rotatably mounted. The compression mechanism 21 which compresses the fluid sucked by the fixed scroll 2, the movable scroll 20, etc. is comprised. In addition, the needle bearing 22 is accommodated in the normal boss | hub part 24a protruding in the back surface (right side in FIG. 1) of the movable scroll substrate 24 in the movable scroll 20. As shown in FIG. The bearing mechanism 23 of the movable scroll 20 is formed by the needle bearing 22 and the radial bearing 10.

The fixed scroll 2 has a vortex-shaped, so-called helical fixed swirl wall (wrap) 28 which is provided on one side of the disk-shaped fixed scroll substrate 26. Similarly, the movable scroll 20 has a movable vortex wall (wrap) 30 of a phase (spiral shape) that stands on one side of a disk-shaped movable scroll substrate 24. Each scroll is arranged such that the vortex walls 28 and 30 mesh with each other.

The fixed scroll substrate 26 and the fixed swirl wall 28 of the fixed scroll 2, the movable scroll substrate 24 and the movable swirl wall 30 of the movable scroll 20 are the fixed swirl wall 28 and the movable swirl wall. The sliding contact at the sliding contact portion (multiple points) 30 forms a crescent compression chamber (closed space) 32. The movable scroll 20 revolves (orbits) in accordance with the rotation (orbiting movement) of the eccentric shaft 14, and the counterweight 18 cancels the centrifugal force due to the revolution of the movable scroll 20 at that time. The drive shaft 8 is driven by the eccentric shaft 14, the bush 16 and the eccentric shaft 14, which are integrally rotated with the drive shaft 8, and the needle bearing 22 sandwiched between the boss portion 24a of the movable scroll 20. Rotational force is transmitted to the movable scroll 20 as an orbital motion.

In the end face of the center housing 4, a plurality of (for example, four) autorotating recesses 34 are formed at equal intervals on the same circumference line. The fixed pin 36 fixed to the center housing 4 and the movable pin 38 fixed to the movable scroll substrate 24 are fixedly mounted in a state of being inserted into the recess 34. The movable scroll 20 is prevented from rotating by the recess 34, the fixing pin 36, and the movable pin 38 in accordance with the rotation of the eccentric shaft 14. That is, the rotation prevention mechanism of the movable scroll 20 is formed by the recessed part 34, the fixing pin 36, and the movable pin 38. As shown in FIG.

The fixed scroll substrate 26 is provided with a reed valve type discharge valve 52 that opens and closes the discharge hole 50. The discharge valve 52 includes a reed valve 54 having a shape corresponding to the discharge hole 50, a valve press 56 supporting the reed valve 54, a reed valve 54, and a valve press 56. It has a fixing bolt 58 fixed to the fixed scroll substrate 26, and is accommodated in the discharge chamber 25 formed in the fixed scroll substrate 26. In addition, the opening / closing operation of the reed valve 54 is performed by the compression difference between the compression chamber 32 and the discharge chamber 25 communicating with the discharge hole 50. That is, when the pressure on the compression chamber 32 side is higher than the pressure on the discharge chamber 25 side, the reed valve 54 is opened, and the pressure on the compression chamber 32 side is higher than the pressure on the discharge chamber 25 side. In the low case, the reed valve 54 is closed. Moreover, the valve press 56 is comprised so that the reed valve 54 may be supported and the maximum opening degree of the reed valve 54 may be regulated. The discharge chamber 25 is covered by the rear cover 51, and the discharge pipe 105 of the air conditioning circuit is connected to the outlet port 51a of the rear cover 51.

The inverter 60 which controls the electric motor 49 is attached to the outer peripheral part of the casing which consists of the fixed scroll 2, the center housing 4, and the motor housing 6. As shown in FIG. The inverter 60 has a relatively high heat generating switching element 62, a relatively low heat generating capacitor 64 and the like, and these components are divided into a high heat generating component and a low heat generating component and housed in the inverter case 70. It is. The switching element 62 is disposed on the outer periphery of the cylinder portion 70a of the inverter case 70, and the capacitor 64 is disposed on the mounting substrate 65. One end of the cylinder portion 70a of the inverter case 70 is connected to the suction port 44, and the other end thereof is connected to the suction pipe 107 of the air conditioning circuit.

In addition, the switching element 62 in the unit housing 70 and the electric motor 49 in the motor housing 6 include three conductive pins 66 penetrating into the motor housing 6 and into the unit housing 70. It is connected by the conducting wires 67 and 68, and the electric power required for the drive of the electric motor 49 is supplied through these conducting pins 66 and the conducting wires 67 and 68. As shown in FIG. This conducting pin 66, the conducting wire 68, or the vicinity thereof corresponds to the electrical connection part in this invention.

Moreover, the connection part of the conducting wire 68 and the stator coil 46a of the electric motor 49 is provided in the compression mechanism side of the electric motor 49. As shown in FIG. Moreover, the inverter 60 is integrated with the housing, and the connection part of the electric motor 49 and the inverter 60 is provided in the outer peripheral part of the radial direction of a housing. That is, compared with the case where an inverter etc. are provided in the outer peripheral part of a horizontal direction, it is a small magnitude which suppressed the shaft length as much as possible.

In addition, connecting portions of the electric motor 49 and the inverter 60 are provided at positions close to each other. Thereby, the electric motor 49 and the inverter 60 can be connected in the shortest distance as much as possible. Therefore, the length of the connecting member can be shortened, and the performance can be improved by reducing the material cost, weight reduction and voltage drop.

The stator 46 is fixedly mounted on the inner circumferential surface of the motor housing 6, and the rotor 48 is fixedly mounted on the drive shaft 8. The electric motor 49 is comprised by the drive shaft 8, the stator 46, the rotor 48, etc., and the rotor 48 and the drive shaft 8 are integrated by the energization of the stator 46 to the stator coil 46a. To rotate. The electric motor 49 is housed in a sealed motor chamber 45 formed by the motor housing 6 and the center housing 4.

As the eccentric shaft 14 of the drive shaft 8 rotates, the movable scroll 20 revolves (orbits), and the fluid introduced from the suction port 44 formed in the fixed scroll causes the edges of both scrolls 2 and 20 to edge. It flows in between the fixed scroll substrate 26 and the movable scroll substrate 24 from the side. In addition, the movable pin 38 slides along the circumferential surface of the fixing pin 36 in accordance with the revolution of the movable scroll 20. Then, when the eccentric shaft 14 rotates, the movable scroll 20 mounted on the eccentric shaft 14 through the needle bearing 22 so as to be relatively rotatable does not rotate but rotates around the center axis of the drive shaft 8. Idle. As the movable scroll 20 revolves, the fluid introduced from the suction port 44 flows into the compression chamber 32 and is led to a high pressure by being directed toward the center of the fixed scroll 2 while increasing the degree of compression. Then, the pressurized fluid flows into the discharge hole 50 which is formed at the center position of the fixed scroll substrate 26 and communicates with the compression chamber 32 at the highest pressure. Then, the pressurized fluid is transferred to the discharge pipe 105 of the air conditioning circuit through the outlet 51a.

In the center housing 4 which partitions the compression mechanism 21 side and the motor chamber 45, the suction region in the flow path of the fluid from suction to discharge formed in the compression mechanism 21 side is communicated with the motor chamber 45. A communication channel 47 is provided. In other words, the sucked fluid passes through the space 47a formed between the outer circumferential surface of the movable scroll substrate 24 and the inner wall surface of the scroll accommodating space for accommodating the movable scroll substrate 24. The space 47a It communicates with the motor chamber 45 by the communication hole 47b provided in this center housing 4. The communication path 47 is comprised by the said space 47a and the communication hole 47b, and this communication path 47 is located in the position of the movable scroll substrate 24 which revolves in the scroll accommodating space during the operation of the compressor. Regardless of the flow path of the fluid, communication is always maintained. For this reason, heat transfer occurs through the communication path 47 between the fluid on the flow path side and the fluid on the motor chamber 45 side. That is, the heat on the motor chamber 45 side, which is the high heat side, moves to the flow path side, and the electric motor 49 is cooled by this heat movement. In addition, when a pressure difference occurs between the motor chamber 45 and the suction region, fluid flows through the communication path 47 between the motor chamber 45 and the suction region. Therefore, heat is moved in accordance with the fluid flow, and the electric motor 49 is cooled. In this way, overheating of the electric motor 49 is prevented.

The cooling described above is so-called "static cooling" which does not involve a large flow of the fluid, unlike the conventional method of using the inside of the motor chamber as a passage for the fluid. The fluid directly involved in such "static cooling" is a part of the fluid which flows through the distribution path, and does not raise the temperature of the whole fluid significantly. For this reason, the problem that a compression efficiency falls by suppressing increase of the specific volume of a fluid can be eliminated.

In addition, in this embodiment, although the structure which cools the inverter 60 is employ | adopted by the fluid sucked in, the calorific value of the inverter 60 is very small compared with the calorific value of the electric motor 49. As shown in FIG. Therefore, as compared with the case where all the suction fluids are distributed in the motor chamber 45 to cool the electric motor 49, the temperature rise of the suction fluid when cooling the inverter 60 with the suction fluid is insignificant and the compression efficiency is lowered. It is not too soon.

In addition, in this embodiment, since a low temperature suction fluid is used for cooling the electric motor 49, a higher cooling effect can be obtained as compared with the discharge fluid. Moreover, according to the structure which guides a suction fluid to the motor chamber 45, it is not necessary to provide a seal material around the drive shaft 8 which transmits the driving force of the electric motor 49 to the compression mechanism 21. As shown in FIG. The structure is simple and advantageous in cost.

In addition, in this embodiment, the high pressure hose 106 of the discharge piping 105 and the low pressure hose 108 of the suction piping 107 are formed using a rubber material. For this reason, as described above, in the air conditioning apparatus 100 used especially outdoors, minute moisture enters the air conditioning circuit through the high pressure hose 106, the low pressure hose 108, and the like. This water circulates in the air conditioning circuit together with the HFC refrigerant and the PVE refrigerant oil. At this time, when moisture enters the motor chamber 45 from the communication path 47 in the scroll compressor 1 and the insulation resistance decreases, for example, a short circuit is likely to occur at or near the conductive wire 68 itself. By the way, in this embodiment, since the PVE system refrigeration oil which has PVE as a main component is used, even if moisture is mixed in an air conditioning circuit, the fall of insulation resistance can be suppressed as much as possible.

That is, the present inventors earnestly examined the influence that various refrigerator oils have on electrical insulation in preventing the electrical insulation from falling even if moisture is mixed in an air conditioning circuit. As a result, the present inventors have succeeded in finding that the problem of the electrical insulation of the fluid can be solved by maintaining the lubricity of the refrigerant by using the PVE refrigerant oil mainly containing PVE as the refrigerant oil for the HFC refrigerant.

As shown in Fig. 3, in the graph showing the correlation between the water concentration in PVE and the insulation resistance, the PVE system refrigeration oil has higher insulation resistance than the ester system refrigeration oil. Able to know. The insulation resistance is maintained at a relatively high level until the moisture becomes saturated. As a result, it was confirmed that the rubber material was used for the piping of the air conditioning circuit, so that even when moisture easily enters the air conditioning circuit, it is effective to suppress the decrease in the insulation resistance as much as possible. Therefore, even if the electric connection part of the electric motor 49, for example, the conduction pin 66 or the conducting wire 68, is in direct contact with the fluid, the insulation resistance of the fluid is kept high by the PVE. The occurrence of a short circuit can be avoided.

In addition, the electrical insulation performance using PVE system refrigeration oil is the use conditions assumed by the scroll compressor 1 of this embodiment, for example, temperature: -30-150 [degreeC], pressure: 0.2-2.5 [MPaG], Viscosity: There was no problem in 5-20 [cSt] (@ 100 degreeC).

As described above, according to the present embodiment, in the vehicle air conditioner 100, the electrical insulation of the air conditioning circuit is reduced as much as possible, and for example, the conductive pin 66 and the conductive wire ( The occurrence of a short circuit in the vicinity of 68) can be avoided. In particular, it is especially effective for the air-conditioning apparatus in which the structure in which the moisture in outside air enters the air conditioning circuit, ie, the scroll compressor 1 is directly attached to the engine E, and the piping in the vicinity is made of rubber material. .

In addition, this invention is not limited only to the said embodiment, A various application and a deformation | transformation are conceivable. For example, each of the following forms may be implemented by applying the above embodiment.

(A) Although the above embodiment has described a case in which a fluid in which a refrigeration oil containing PVE as a main component is mixed in an HFC system refrigerant is circulated in an air conditioning circuit, other fluids may be mixed and used. For example, tricredyl phosphate (TCP) as an extreme pressure additive may be mixed to prevent the seizure of the compressor, or an antioxidant (for example, DBPC) may be mixed for the oxidation stability of the refrigeration oil.

(B) In the above embodiment, the scroll compressor is described, but the present invention is applied to another type of compressor, for example, a reciprocating compressor that compresses refrigerant by reciprocating a piston in a cylinder bore. You may.

(C) Moreover, in the said embodiment, although it described about the air conditioner 100 of a motor vehicle, this invention can also be applied to the air conditioner of vehicles other than an automobile.

As described above, according to the present invention, it is possible to realize a vehicle air conditioning technique effective for suppressing the fall of the electrical insulation in the vehicle air conditioner as much as possible.

Claims (5)

A vehicle air conditioner compressor having a conductive portion communicating with a flow path from suction to discharge of fluid and compressing the fluid in the flow path to increase pressure, and discharge the fluid to an air conditioning circuit of the vehicle. And said refrigerant contains a refrigerant oil containing polyvinyl ether oil as a main component in a refrigerant. 2. The compressor as claimed in claim 1, further comprising a compressor mechanism for compressing the fluid, an electric motor for driving the compressor mechanism, and an electrical connection portion of the motor. And the electrical connection portion is the conductive portion, and the electrical connection portion is configured to communicate with the distribution path. 3. A sealed motor chamber for accommodating the electric motor, and a communication path for communicating the motor chamber with the flow path. The electric connection unit of the electric motor is configured to communicate with the distribution path via the communication path. 4. The vehicle air conditioner according to any one of claims 1 to 3, wherein the compressor itself is mounted on a vehicle engine which is a driving source of the vehicle, and the distribution path is connected to a pipe formed using a rubber material. Compressor. An air conditioning apparatus comprising the vehicle air conditioning compressor according to any one of claims 1 to 3, and configured to circulate the fluid to the air conditioning circuit through the vehicle air conditioning compressor to perform air conditioning. .