JP4043233B2 - Gas compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure of a vane rotary type gas compressor used for an air conditioner for a vehicle or the like.
[0002]
[Prior art]
A gas compressor used for compressing a refrigerant such as an air conditioner is provided with a rotor provided with a plurality of vanes in a cylinder having an inner peripheral surface arranged in a compressor case and having a substantially elliptical shape. The partitioned space forms a compression chamber that repeats volume changes, and the refrigerant gas sucked into the compression chamber from the suction port is compressed and discharged from the discharge port.
[0003]
FIG. 4 is a longitudinal sectional view showing such a conventional gas compressor, and FIG. 5 is a view showing a cylinder and a rotor in a cross section taken along line AA in FIG. 4 corresponds to a cross section taken along the line BB in FIG.
A compressor case 10 is formed by a housing 11 of one end opening type and a front head 12 attached to the opening side thereof. A cylinder 40 having a substantially elliptical inner periphery is disposed between the front side block 20 and the rear side block 30 in the housing 11, and a rotor 50 including a plurality of vanes 58 is rotatably provided in the cylinder 40. Yes.
[0004]
A rotary shaft 51 that rotates integrally with the rotor 50 passes through the front side block 20, the front end side extends from the lip seal 18 of the compressor case end wall to the outside of the front head 12, and the rear end is a through hole provided in the rear side block 30. It is supported by the support hole 32. An electromagnetic clutch 25 having a pulley 24 is attached to the front end of the rotary shaft 51 so as to receive a rotational driving force from a crank pulley of an engine (not shown).
[0005]
A plurality of slit-like vane grooves 56 are radially formed on the outer peripheral surface side of the rotor 50, and vanes 58 are attached to these vane grooves 56, respectively. The vane 58 is urged toward the inner peripheral surface of the cylinder 40 by centrifugal force and hydraulic pressure applied to the back pressure chamber 59 formed at the bottom of the vane groove 56 when the rotor 50 rotates. The inside of the cylinder 40 is partitioned into a plurality of small chambers by a rotor 50 and a vane 58, and a compression chamber 48 is formed that repeatedly changes in volume as the rotor 50 rotates. As a result, a vane rotary compressor is formed.
[0006]
A front-side suction chamber 13 having a refrigerant gas suction port 14 is formed between the front head 12 and the front side block 20.
The front side block 20 has a suction port 22 that allows the front suction chamber 13 and the compression chamber 48 to communicate with each other.
[0007]
The refrigerant gas flowing into the front suction chamber 13 from the refrigerant gas suction port 14 is sucked into the compression chamber 48 from the suction port 22 formed in the front side block 20. Further, the cylinder 40 is provided with a communication hole 41 communicating with the rear side suction port 31 formed in the rear side block 30 in the axial direction, and the rear side suction port 31 from the front side suction chamber 13 through the communication hole 41. Also, the refrigerant gas is sucked into the compression chamber 48.
[0008]
A discharge chamber 15 is formed between the sealed side of the housing 11 and the rear side block 30 and includes a refrigerant gas discharge port 16.
A cyclone block 60 having an oil separator 62 is attached to the discharge chamber 15 side of the rear side block 30. The cyclone block 60 forms a sealed space R with a seal ring 64 sandwiched between the cyclone block 60 and the boss portion 38 in which the through support hole 32 of the rear side block 30 that supports the rear end of the rotating shaft 51 is formed.
[0009]
In the vicinity of the short diameter portion of the cylinder 40, the discharge chamber 44 is cut out at the outer peripheral portion to form a thin portion, and the discharge port 42 is opened in the thin portion. A reed valve 43 is provided at the discharge port 42.
The refrigerant gas discharged from the discharge port 42 is discharged from the discharge chamber 44 to the discharge chamber 15 via the oil separator 62.
The suction port 22 and the discharge port 42 are provided at two positions along the periphery of the cylinder 40 symmetrically with respect to the rotation shaft 51 of the rotor 50.
[0010]
When the rotor 50 rotates, the refrigerant gas flowing into the refrigerant gas intake port 14 is drawn from the front suction chamber 13 through the suction port 22 into the compression chamber 48. Then, after being compressed in the compression chamber 48, it is discharged from the discharge port 42, and the refrigerant gas is supplied to the outside through the discharge chamber 15 from the refrigerant gas discharge port 16.
[0011]
In such a gas compressor, the lubricating oil stored in the discharge chamber 15 is guided in order to lubricate the through support hole 32 of the rotating shaft 51 and supply the hydraulic pressure to the back pressure chamber 59 of the vane groove 56. ing.
That is, in the conventional gas compressor, the rear side block 30 is formed with an oil passage 33 that opens at the bottom of the discharge chamber 15 and reaches the side wall of the through support hole 32, and the surface of the rear side block 30 that faces the rotor 50. A recess 35 and a small recess 37 are provided so as to communicate with the back pressure chamber 59 of the vane groove 56.
[0012]
The concave portion 35 has a constricted portion 35a in the front shape, and the small concave portion 37 is disposed radially outward of the constricted portion 35a. The small concave portion 37 communicates with the back pressure chamber 59 of the vane groove 56 that supports the vane 58 that passes through the discharge port 42 of the cylinder 40, and the concave portion 35 communicates with the back pressure chamber 59 of the vane groove 56 that supports other vanes 58. Are associated with each other.
[0013]
The sealed space R between the cyclone block 60 and the rear side block 30 and the recess 35 are connected by a communication path 34, and the vicinity of the through hole 32 of the oil passage 33 and the small recess 37 are connected by a communication path 36.
The lubricating oil which is pushed by the discharge pressure of the discharge chamber 15 and reaches the side wall of the through support hole 32 through the oil passage 33 passes through the gap between the through support hole 32 and the rotary shaft 51 to the recess 35 and the sealed space R. It flows to the small recess 37 by the communication path 36.
[0014]
A through hole 46 connected to the oil passage 33 of the rear side block 30 is provided at the bottom of the cylinder 40, and the through hole 46 and the rotary shaft support of the front side block 20 are supported by the oil passage 26 formed in the front side block 20. The part 23 is connected to guide the lubricating oil to the concave part 27 formed on the surface of the support part 23 and the front side block 20 facing the rotor 50.
[0015]
[Problems to be solved by the invention]
In the configuration as described above, the lubricating oil in the sealed space R between the cyclone block 60 and the rear side block 30 facing the rear end of the rotating shaft 51 of the rotor 50 is discharged between the through support hole 32 and the rotating shaft 51. The pressure is reduced by the squeezing action when passing through the minute gap, resulting in an intermediate pressure state slightly close to the discharge pressure. This intermediate pressure is also an average pressure of the plurality of vane back pressures because the sealed space R communicates with the recess 35 by the communication passage 34 and thus communicates with the back pressure chambers 59 of the plurality of vane grooves 56.
[0016]
Here, while the rear end of the rotating shaft 51 receives the intermediate pressure of the sealed space R, the outside of the front head 12 from which the front end of the rotating shaft 51 protrudes is atmospheric pressure. 50 is urged to the front side. The rotor 50 urged to the front side is pressed against the opposing surface of the front side block 20, and there is a risk of increasing the required driving force and causing wear and seizure of the contact surface. On the other hand, since the gap between the opposed surfaces of the rear side block 30 and the rotor 50 becomes large, the refrigerant leak increases and the performance is deteriorated. This problem becomes serious when CO2 or the like whose discharge pressure or the like is set to be extremely higher than that of R134a or the like is used as the refrigerant.
[0017]
Therefore, in view of the above-described problems, the present invention provides a gas compressor that suppresses generation of a pressing force that urges the rotor in the axial direction during operation, and prevents an increase in driving force, operational failure, and performance degradation due to leakage. The purpose is to do.
[0018]
[Means for Solving the Problems]
For this reason, the present invention of claim 1 provides a rotor having a plurality of vanes forming a compression chamber in a cylinder whose inner peripheral surface is disposed between a front side block and a rear side block in a compressor case. The front end of the rotating shaft is supported in the through hole of the front side block and protrudes from the compressor case, and the rear end of the rotating shaft is supported by the through hole of the rear side block. In a gas compressor having a suction chamber and a discharge chamber on the rear side block side, the front side block is provided with a suction port that connects the suction chamber and the compression chamber, and around the discharge chamber side opening of the through hole of the rear side block. cover, cut off from the compression chamber a sealed space is provided, provided on the rotating shaft connecting the suction chamber with the closed space It was assumed to have the input pressure communication passage.
Since the sealed space where the rear end of the rotating shaft faces is in communication with the suction pressure side and becomes a low pressure, generation of force for urging the rotor to the front side is suppressed.
In addition, since the suction pressure communication passage is provided on the rotation shaft and connects the sealed space and the suction chamber, the suction pressure communication passage can be formed by simple processing on the rotation shaft, and the suction pressure can be guided to the sealed space. .
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described by way of examples.
FIG. 1 is a longitudinal sectional view according to the first embodiment.
The refrigerant gas flowing into the front suction chamber 13 from the refrigerant gas suction port 14 is sucked into the compression chamber 48 from the suction port 22 formed in the front side block 20. Further, the cylinder 40 is provided with a communication hole 41 in the axial direction that communicates with the rear side suction port 31 formed in the rear side block 30A, and the rear side suction port 31 passes through the communication hole 41 from the front side suction chamber 13. Also, the refrigerant gas is sucked into the compression chamber 48.
The compressed refrigerant is discharged from the discharge port 42 (see FIG. 5) on the side wall of the cylinder, and is guided to the discharge chamber 15 through the cyclone block 60.
[0020]
A sealed space R is formed between the rear side block 30A and the cyclone block 60 attached to the discharge chamber 15 side. The rear side block 30 </ b> A is provided with a through support hole 32 that opens into the sealed space R, and the rotating shaft 51 of the rotor 50 is supported in the through support hole 32.
A front end side of the rotating shaft 51 passes through the front side block 20, extends outward of the front head 12, and an electromagnetic clutch 25 having a pulley 24 is attached.
[0021]
The rear side block 30A is formed with an oil passage 33 that opens at the bottom of the discharge chamber 15 and reaches the side wall of the through support hole 32. The back pressure of the vane groove 56 is formed on the surface of the rear side block 30A that faces the rotor 50. A recess 35 and a small recess 37 are provided so as to communicate with the chamber 59.
The vicinity of the through hole 32 of the oil passage 33 and the small concave portion 37 are connected by a communication passage 36.
The lubricating oil which is pushed by the discharge pressure of the discharge chamber 15 and reaches the side wall of the through support hole 32 through the oil passage 33 passes through the gap between the through support hole 32 and the rotary shaft 51 to the recess 35 and the sealed space R. It flows to the small recess 37 by the communication path 36.
The above configuration is the same as the configuration shown in FIGS. 4 and 5 although the rear side block 30 is changed to the rear side block 30A.
[0022]
In the present embodiment, as shown in FIG. 1 and FIG. 2 in which the rear side block 30A is viewed from the cylinder 40 side, a sealed space R between the cyclone block 60 and the rear side block 30A is formed in the communication passage 39 formed in the rear side block 30A. To the rear-side suction port 31. The communication path 39 includes a first path 39a extending in the axial direction from an end surface facing the sealed space R of the boss portion 38 of the rear side block 30A, and a second path 39b connecting the first path and the rear-side suction port 31. The second path 39b is formed by drilling at an angle from the rear suction port 31 side toward the first path 39a.
Other configurations are the same as the configurations shown in FIGS. 4 and 5, and a description thereof will be omitted.
[0023]
The present embodiment is configured as described above, and since the sealed space R is communicated with the rear-side suction port 31 through the communication path 39, the sealed space R where the rear end of the rotating shaft 51 faces becomes the suction pressure. Therefore, the force for urging the rear end of the rotating shaft 51 to the front side is greatly reduced. The small concave portion 37 formed on the surface facing the rotor 50 of the rear side block 30A is supplied with lubricating oil having a discharge pressure from the oil passage 33 through the communication passage 36, but the area of the small concave portion 37 is small. As a result, no remarkable force for urging the rotor to the front side is generated.
[0024]
Further, the lubricating oil that has flowed into the sealed space R through the clearance between the through support hole 32 and the rotary shaft 51 enters the cylinder 40 from the rear side suction port 31 and is compressed again in the compression chamber together with the suctioned refrigerant. 40 is discharged from the discharge port 42 to the discharge chamber 14 while lubricating each part in the tank 40.
Thereby, the rotor 50 is not pressed against the front side block 20, and unnecessary increase in required driving force, wear on the contact surface, and seizure are avoided. Further, since the internal leakage of the lubricating oil is reduced, the performance as a compressor is improved.
[0025]
FIG. 3 shows a second embodiment.
In this embodiment, a communication passage 55 is provided on the rotary shaft 51A instead of the communication passage 39 that allows the sealed space R to communicate with the rear-side suction port 31.
The communication path 55 of the rotating shaft 51A includes a shaft hole 55a extending from the rear end face facing the sealed space R between the cyclone block 60 and the rear side block 30B to the front of the lip seal 18 on the central axis, and a front side suction in the front head 12. It consists of a lateral hole 55 b that opens into the chamber 13.
Other configurations are the same as those of the first embodiment shown in FIG.
[0026]
In the present embodiment, since the sealed space R communicates with the front suction chamber 13 through the communication passage 55, the sealed space R facing the rear end of the rotating shaft 51A similarly has suction pressure, and the rear end of the rotating shaft 51A is The force for urging the front side is greatly reduced.
Therefore, as in the previous embodiment, the rotor 40 is not pressed against the front side block 20, and unnecessary increase in required driving force, wear on the contact surface, and seizure are avoided. Further, since the internal leakage of the lubricating oil is reduced, the performance as a compressor is improved.
[0027]
【The invention's effect】
As described above, the present invention supports the front end side of the rotating shaft of the rotor in the through support hole of the front side block and protrudes from the compressor case to the outside, and supports the rear end of the rotating shaft in the through support hole of the rear side block. The vane rotary type gas compressor is provided with a sealed space that covers the periphery of the opening on the discharge chamber side of the through hole of the rear side block, and has a suction pressure communication path that communicates the sealed space with the suction pressure side. As a result, the pressure applied to the rear end of the rotating shaft in the sealed space is low, so that the rotor is not pressed against the front side block, and the required driving force is increased unnecessarily, the contact surface is worn, Attaching is avoided. Moreover, since the internal leak of lubricating oil also decreases, it has the effect of improving the performance as a compressor.
[0028]
Since the suction pressure communication path is provided on the rotation shaft and connects the sealed space and the suction chamber, the suction pressure communication path can be formed by simple processing on the rotation shaft, and the suction pressure can be guided to the sealed space.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a first embodiment of the present invention.
FIG. 2 is a view of a rear side block as viewed from the cylinder side.
FIG. 3 is a longitudinal sectional view showing a second embodiment.
FIG. 4 is a longitudinal sectional view showing a conventional gas compressor.
5 is a cross-sectional view taken along line AA in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Compressor case 11 Housing 12 Front head 13 Front side suction chamber 14 Refrigerant gas suction port 15 Discharge chamber 16 Refrigerant gas discharge port 18 Lip seal 20 Front side block 22 Suction port 23 Rotating shaft support part 26 Oil path 24 Pulley 27 Recess 30 30A, 30B Rear side block 31 Rear side suction port 32 Through support hole 33 Oil passage 34, 36 Communication passage 35 Recess 35a Constriction portion 37 Small recess 38 Boss portion 39 Communication passage 39a First passage 39b Second passage 40 Cylinder 41 Communication hole 42 Discharge port 43 Reed valve 44 Discharge chamber 46 Through hole 48 Compression chamber 50 Rotor 51, 51A Rotating shaft 55 Communication passage 55a Shaft hole 55b Horizontal hole 56 Vane groove 58 Vane 59 Back pressure chamber 60 Cyclone block 62 Oil separator 64 Seal ring R Sealing space

Claims (1)

A rotor having a plurality of vanes forming a compression chamber in a cylinder having a substantially elliptical inner peripheral surface arranged between a front side block and a rear side block in a compressor case, and a front side block on the front end side of the rotating shaft thereof The rear end of the rotating shaft is supported by the through support hole of the rear side block, and the suction chamber is provided on the front side block side and the discharge chamber is provided on the rear side block side. In the arranged gas compressor,
The front side block is provided with a suction port that communicates the suction chamber and the compression chamber,
Covering around the discharge chamber side opening of the through hole of the rear side block, a sealed space is provided that is blocked from the compression chamber ,
A gas compressor comprising a suction pressure communication path provided on the rotating shaft and connecting the sealed space and a suction chamber .

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