JP2004360643A - Scroll fluid machinery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide scroll fluid machinery capable of leading working gas, by simple structure, to a portion where the working gas including an atomized lubricating oil is hard to reach and lubrication is requested. <P>SOLUTION: This scroll fluid machinery, i.e., a compressor comprises a lead-in hole 96 formed through an eccentric bush 66 supporting the large diameter end part 34 of a rotating shaft 30 or a movable scroll 54. The lead-in hole 96 comprises an opening end close to a lead end face 90 on a preceding side in the swing motion of a counterweight 70. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a scroll-type fluid machine suitable as a compressor for a refrigeration circuit included in, for example, an automotive air conditioning system.
[0002]
[Prior art]
This type of scroll-type fluid machine, that is, a scroll-type compressor uses a working gas containing a mist-like lubricating oil, and this working gas acts as a refrigerant of a refrigeration circuit and is used in various parts of the scroll-type compressor. Supply lubricating oil.
That is, since the inside of the housing of the scroll compressor is filled with the working gas, the working gas in the housing comes into contact with the bearing or the like, so that the mist-like lubricating oil adheres to the bearing or the like, that is, is supplied. be able to.
[0003]
However, in addition to bearings, there are other parts in the housing that require lubrication, such as a shaft sealing unit such as a lip seal that hermetically seals the rotating shaft against the housing, and a crankpin of the rotating shaft. The unit and the crankpin are arranged in a closed area where the working gas does not sufficiently reach due to the presence of a bearing or the like. The crank pin is a member that supports the scroll unit, that is, the movable scroll via an eccentric bush and a bearing, and imparts a turning motion to the movable scroll.
[0004]
For this reason, a scroll type in which an oil supply hole is formed at the large-diameter end portion of the rotating shaft on which the crank pin is protruded, and the working gas is guided toward the shaft sealing unit through the oil supply hole. Through holes are formed not only in the compressor (Patent Document 1) and the large-diameter end of the rotating shaft, but also in each of the counterweight and the eccentric bush for the orbiting scroll, and the bearing is used as an open-type rolling bearing to circulate working gas. 2. Description of the Related Art There is known a scroll compressor in which a route is secured (Patent Document 2).
[0005]
[Patent Document 1]
JP-A-11-30188 [Patent Document 2]
JP-A-11-182461 [0006]
[Problems to be solved by the invention]
However, any of the scroll-type compressors disclosed in the above-mentioned publications merely has an oil supply hole or a through hole formed therein, and does not reliably guarantee the flow of the working gas into the oil supply hole or the through hole. .
The present invention has been made on the basis of the above-described circumstances, and has as its object a simple configuration, in which a lubricating oil is supplied to a shaft sealing unit and a crankpin arranged in a closed area where working gas is difficult to reach. An object of the present invention is to provide a scroll-type fluid machine capable of reliably supplying a scroll type fluid machine.
[0007]
[Means for Solving the Problems]
A scroll-type fluid machine according to the present invention that achieves the above object has a housing, a large-diameter end portion extending in the housing and having a small-diameter shaft portion at one end and a crankpin at the other end, and a small-diameter shaft portion. A rotary shaft rotatably supported by a housing via a bearing, and a small-diameter shaft portion of the rotary shaft, and hermetically sealing the small-diameter shaft portion between the bearings with respect to the housing. A shaft sealing unit, which is housed in a housing and driven by a crank pin of a rotating shaft, performs a series of processes of suction, compression and discharge of a working gas containing a mist of lubricating oil. And a scroll unit for filling the housing into the housing.
[0008]
The scroll unit is rotatably provided on the crank pin, and is supported by an eccentric bush that is rotatably mounted on the crank pin and is spaced apart from the large-diameter end of the rotating shaft via an eccentric bearing. A movable scroll that performs the above-described series of processes in cooperation with a fixed scroll, and a counterweight that is attached to the eccentric bush and orbits with the movable scroll to secure a balance with the movable scroll. The large-diameter end and the eccentric bush are located between the portion and the eccentric bush, extend in the radial direction thereof, and have a lead end face that is a leading side and a tail end face that is a trailing side with respect to the turning direction of the counterweight. , A counterweight, one of the large diameter end and the eccentric bush, and penetrates in the axial direction thereof. And a through-hole having an open end proximate to one lead surfaces and a tail surface (claim 1).
[0009]
According to the scroll-type fluid machine described above, when the counterweight rotates together with the orbiting scroll, the lead surface pushes the working gas in the housing to pressurize the working gas in the vicinity thereof, while the tail surface pushes the working gas. Escapes from the working gas to reduce the pressure of the working gas in the vicinity.
Therefore, if the opening end of the through hole is close to the lead surface, pressurization of the working gas by the lead surface forcibly introduces the working gas into the through hole from the opening end. Is supplied to the part requiring lubrication in the closed area. On the other hand, if the opening end of the through hole is close to the tail surface, the pressure reduction of the working gas by the tail surface forcibly sucks the working gas in the through hole from the opening end and makes the inside of the closed area a negative pressure. Therefore, the working gas around the closed region actively flows into the closed region through the gap in the bearing, and is supplied to a portion requiring lubrication.
[0010]
Specifically, the through-hole is an introduction hole which is provided at the large-diameter end of the rotating shaft and whose open end is close to the lead surface (claim 2). In this case, the lead end surface may have a curved portion extending along the peripheral edge of the opening end (claim 3) or may have an inclined portion extending toward the opening end (claim 4). The curved portion of the lead end surface causes the extruded working gas to swirl along the periphery of the open end, and the inclined portion of the lead end surface deflects the extruded working gas toward the open end, and in each case the introduction hole To the working gas more actively.
[0011]
Further, the through-hole may include a suction hole separately from the above-described introduction hole, which is also provided at the large-diameter end portion and whose open end is close to the tail surface (claim 5). Preferably, it is located farther away from the axis of the large diameter end than the hole.
The depressurizing action of the working gas by the tail surface sucks the working gas in the closed area through the suction hole, and this suction promotes the introduction of new working gas into the introduction hole. When the positions of the introduction hole and the suction hole are shifted from each other in the radial direction of the large-diameter end portion, the introduction flow of the working gas into the closed area and the suction flow of the working gas from the closed area interfere with each other. Therefore, the working gas in the closed area is quickly ventilated.
[0012]
When the bearing between the large-diameter end of the rotating shaft and the housing is an open-type rolling bearing that allows the flow of the working gas, the through hole is provided at the large-diameter end and the open end is close to the tail surface. It may be a suction hole that has been formed (claim 7).
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a refrigeration circuit of an automotive air conditioning system.
The refrigeration circuit includes a scroll-type fluid machine, that is, a compressor 4 disposed in an engine room 2 of an automobile. The compressor 4 includes an instrument panel 8 that partitions the engine room 2 from the vehicle room 6. The evaporator 12 is connected to the evaporator 12 through a circulation line 14, and a condenser 16 and an expansion valve 18 are interposed in the outward path of the circulation circuit 14.
[0014]
Power is transmitted from the engine 15 to the scroll type compressor 4 via the drive belt 17, and the refrigerant filling the refrigeration circuit, that is, the working gas containing the mist-like lubricating oil is sucked in from the return path of the circulation line 14. The compressed working gas is discharged toward the condenser 16. Thereafter, the compressed working gas is condensed in the condenser 16 and then expanded in the evaporator 12 through the expansion valve 18, and the evaporator 12 exchanges heat between the working gas and the air in the vehicle compartment 6. Is performed to cool the air in the cabin 6. The working gas that has passed through the evaporator 12 is returned to the scroll compressor 4 through the return path of the circulation pipe 14.
[0015]
The details of the scroll compressor 4 are shown in FIG. 2, and the compressor 4 has a housing 20. The housing 20 has a drive casing 22 and a compression casing 24. The drive casing 22 has a stepped cylindrical shape having a large diameter on the compression casing 24 side, and has both open ends. On the other hand, the compression casing 24 has a cup shape opened toward the large-diameter end of the drive casing 22, and the open end is air-tightly fitted to the large-diameter end of the drive casing 22 via a seal ring 26. Is connected to the large-diameter end of the drive casing 22 through the connection screw 28 of the drive casing 22.
[0016]
A rotary shaft 30 is arranged in the drive casing 22, and also has no stepped shape, and has a small-diameter shaft portion 32 at one end and a large-diameter end 34 at the other end.
The large-diameter end 34 of the rotating shaft 30 is rotatably supported by the drive casing 22 via a needle bearing 36. Here, the needle bearing 36 is an open type, and the space on both sides thereof can be freely circulated through the inside.
[0017]
The small-diameter shaft portion 32 of the rotating shaft 30 is also rotatably supported on the small-diameter end of the drive casing 22 via a ball bearing 38.
Further, a shaft sealing unit, that is, a lip seal 40 is disposed between the ball bearing 38 and the needle bearing 36 in the drive casing 22, and the lip seal 40 is opposed to the small-diameter shaft portion 32 of the rotating shaft 30. The inside of the drive casing 22 is air-tightly partitioned in a sliding manner.
[0018]
Further, the small-diameter shaft portion 32 of the rotating shaft 30 projects from the small-diameter end of the drive casing 22, and the drive disk 42 is attached to the projected end via a nut 44. The drive disk 42 is connected to a drive pulley 48 via an electromagnetic clutch 46. The drive pulley 48 has a built-in solenoid of the electromagnetic clutch 46, and is rotatably supported on a small-diameter end of the drive casing 22 via a pulley bearing 50. ing.
[0019]
The drive belt 18 is wound around the drive pulley 48, and the electromagnetic clutch 46 interrupts the drive force transmitted from the drive pulley 48 to the drive disk 42, that is, the rotating shaft 30. Therefore, when the electromagnetic clutch 46 is turned on, the electromagnetic clutch 46 integrally connects the drive pulley 48 and the drive disk 42, and rotates the drive disk 42, that is, the rotating shaft 30, together with the drive pulley 48 in one direction. On the other hand, when the electromagnetic clutch 46 is turned off, the electromagnetic clutch 46 releases the connection between the drive pulley 48 and the drive disk 42, and cuts off the transmission of the power of the rotary shaft 30 from the drive pulley 48.
[0020]
On the other hand, a school unit 52 is accommodated in the compression casing 24, and the scroll unit 52 includes a movable scroll 54 and a fixed scroll 56. The movable scroll 54 and the fixed scroll 56 have spiral wraps 54a and 56a that mesh with each other, and the spiral wraps 54a and 56a cooperate with each other to form a compression chamber 58 through a seal. The compression chamber 58 moves toward the center from the radially outer peripheral side of the spiral wraps 54a and 56a by the orbital movement of the movable scroll 54, and at this time, the volume thereof is reduced.
[0021]
In order to achieve the above-described orbiting movement of the movable scroll 54, the substrate 60 of the movable scroll 54 has a boss 62 protruding toward the drive casing 22 side, and the boss 62 is provided via an open type needle bearing 64. The eccentric bush 66 is rotatably supported. The eccentric bush 66 is supported by a crank pin 68, which eccentrically projects from the large-diameter end 34 of the rotating shaft 30. Accordingly, with the rotation of the rotating shaft 30, the orbiting scroll 54 orbits through the crank pin 68 and the eccentric bush 66.
[0022]
A counterweight 70 is attached to the eccentric bush 66 so as to be sandwiched between the eccentric bush 66 and the large-diameter end portion 34. The counterweight 70 is formed by stacking a plurality of large and small arc-shaped plates. It is a balance weight for the orbiting movement of the orbiting scroll 54. More specifically, the counterweight 70 is attached to the eccentric bush 66 via a connecting pin 71, and rotation around the connecting pin 71 is prevented by the crank pin 68. Therefore, similarly to the movable scroll 54, the counterweight 70 also makes a revolving motion while keeping the revolving posture constant.
[0023]
Further, a ball coupling 72 as a rotation preventing mechanism is interposed between the large-diameter end of the drive casing 22 and the substrate 60 of the movable scroll 54. For example, the ball coupling 72 is supported by the large-diameter end of the drive casing 26 and the substrate 60, respectively, and has a pair of ring plates 74 having annular races at equal intervals in the circumferential direction. The ball 76 is held between the races, and prevents the movable scroll 54 from rotating around the axis of the needle bearing 64.
[0024]
On the other hand, the fixed scroll 56 is fixed in the compression casing 24, and its substrate 78 partitions the inside of the compression casing 24 into a compression chamber 58 side and a discharge chamber 80. A discharge hole 82 is formed in the center of the substrate 78 and is connected to the compression chamber 58. The discharge hole 82 is opened and closed by a reed valve 84 as a discharge valve. The reed valve 84 is mounted on the outer surface of the substrate 78 via bolts together with the valve retainer 86.
[0025]
Although not shown in FIG. 2, a suction port and a discharge port communicating with the compression chamber 58 and the discharge chamber 80 are formed on the peripheral wall of the compression casing 24, and the suction port is provided in the above-described circulation pipe. The outlet is connected to the return path, and the outlet is connected to the outward path of the circulation line.
According to the above-described scroll compressor, the movable scroll 54 orbits through the crank pin 68 and the eccentric bush 66 with the rotation of the rotary shaft 30, and the rotation of the movable scroll 54 It is in a state of being blocked by work. As a result, the orbiting scroll 54 orbits with respect to the fixed scroll 56 while keeping the orbiting posture constant, and this orbiting movement sucks working gas into the compression chamber 58 from the outward path of the circulation pipe through the suction port. Then, the sucked working gas is compressed, and a series of processes for discharging the compressed working gas into the discharge chamber 80 through the reed valve 84 is performed. Thereafter, the compressed working gas is circulated from the discharge chamber 80 through the outlet. It is supplied to the outbound path of the pipeline.
[0026]
On the other hand, the above-described scroll unit 52 can guide a part of the working gas sucked through the suction port into the drive casing 22, whereby the inside of the drive casing 22 is filled with the working gas. Since this working gas contains mist-like lubricating oil, when the working gas comes into contact with the needle bearings 36, 64 and the ball coupling 72 in the drive casing 22, the lubricating oil adheres to these and is lubricated. You.
[0027]
Further, since the needle bearings 36 and 46 are open type, the working gas enters the closed area A formed between the needle bearing 36 and the lip seal 40 through the needle bearing 36, and lubricates the lip seal 40. Will be done again. Further, the working gas that has passed through the needle bearing 46 also enters a closed area B formed between the needle bearing 46 and the orbiting scroll 54, and lubricates the crankpin 68 from both sides.
[0028]
Referring to FIG. 3, the arrangement of the counterweight 70 with respect to the large diameter end 34 of the rotation 30 is specifically shown. In addition, in FIG. 3 and subsequent figures, the counterweight 70 is shown as an integral component for the sake of drawing convenience.
As is apparent from FIG. 3, the counterweight 70 generally has a substantially semicircular disk shape, and only the thickness of the outer peripheral portion is increased. As described above, the radially inner portion of the counterweight 70 is sandwiched between the large-diameter end 34 of the rotating shaft 30 and the eccentric bush 66, and the radially inner portion is interposed between the large-diameter end 34 and the eccentric bush 66. And has an inner end surface 88 extending radially across the large diameter end 34. The inner end surface 88 is formed by the crank pin 68 of the rotating shaft 30 in two regions, that is, the lead end surface 90 on the leading side when viewed in the turning direction C of the counterweight 70 indicated by the arrow in FIG. It is divided into a tail end face 92.
[0029]
In the case of the embodiment shown in FIG. 3, a portion of the lead end face 90 extending from the crank pin 60 to the outer peripheral edge of the large diameter end 34 projects in the turning direction of the counterweight 70 and is perpendicular to the end face of the large diameter end 34. The flat portion 94 is formed. On the other hand, an introduction hole 96 penetrating in the axial direction is formed in the outer peripheral portion of the large-diameter end portion 34, and the introduction hole 96 has an open end close to the flat portion 94 of the lead end face 90. That is, the introduction hole 96 communicates between the internal space on the large-diameter end side of the drive casing 22 and the closed area A (see FIG. 2).
[0030]
In FIG. 3, reference numeral 98 indicates an insertion hole of the connecting pin 71, and the rotation of the counterweight 70 around the connecting pin 71 is prevented during the turning movement of the counterweight 70. The positional relationship between the flat portion 94 of the lead end face 90 and the opening end of the introduction hole 96 is always maintained in the state shown in the figure.
During the turning movement of the counterweight 70, the flat portion 94 of the lead end face 90 pushes the working gas in the drive casing 22 as shown by the arrow D in FIG. 3 and pressurizes the working gas in the vicinity. Therefore, a part of the pressurized working gas is forcibly introduced into the introduction hole 96 through the opening end close to the flat portion 94, and is closed through the introduction hole 96 as shown by an arrow E in FIG. Enter area A.
[0031]
When the working gas is forced to enter the closed area A in this manner, a large amount of the working gas comes into contact with the lip seal 40, so that the lubricating oil can be sufficiently and reliably supplied to the lip seal 40. Thus, the durability of the lip seal 40 can be greatly improved.
Further, since the counterweight 70 is an essential component of the scroll compressor, it is not necessary to add a new part to the compressor for forcibly introducing the working gas into the introduction hole 96. Forced introduction of working gas into the system can be realized with a simple configuration.
[0032]
Further, since the lubrication of the lip seal 40 is sufficiently performed, the amount of the atomized lubricating oil in the working gas, that is, the amount of the sealed oil can be reduced. As a result, the working gas effectively functions as a refrigerant, not only improving the heat exchange efficiency in the evaporator, but also reducing the amount of working gas required in the refrigeration circuit, and providing a compact and inexpensive refrigeration circuit. can do.
[0033]
The present invention is not limited to the above-described embodiment, and various modifications are possible.
The lead end face 90 of the first modified example shown in FIG. 4 is such that a portion located radially outside the large-diameter end portion 34 from the introduction hole 96 is curved along the periphery of the open end of the introduction hole 96. 100. Such a curved portion 100 of the lead end face 90 causes the extruded working gas to swirl along the periphery of the opening end as shown by an arrow F in FIG.
[0034]
The lead end face 90 of the second modification shown in FIG. 5 has an inclined portion 102 that overhangs toward the opening end of the introduction hole 96. The inclined portion 102 of the lead end face 90 deflects the extruded working gas toward the opening end of the introduction hole 96 as is apparent from FIG.
As is clear from FIGS. 5 and 6, the inclined portion 102 is thicker than the portions of the lead end faces 90 on both sides thereof, and the effective pressing area of the working gas is further increased.
[0035]
In the case of the third modification shown in FIG. 7, the large-diameter end portion 34 has a suction hole 104 separately from the introduction hole 96. The suction hole 104 also penetrates the large-diameter end portion 34 and has an open end close to the tail end surface 92 of the counterweight 70. Then, as shown in FIG. 8, assuming that the separation distances between the center of the opening end of the introduction hole 96 and the suction hole 104 and the axis of the large-diameter end 34 are L ₁ and L ₂ , respectively, L ₁ > L ₂ Is established.
[0036]
During the pivoting movement of the counterweight 70, the tail end face 92 escapes from the working gas, so that the working gas in the vicinity thereof is depressurized. Such a depressurizing action forcibly sucks the working gas in the suction hole 104, that is, the above-described closed area A, through the opening end of the suction hole 104.
Accordingly, the introduction of the working gas into the closed area A through the introduction hole 96 and the suction of the working gas through the suction hole 104 are simultaneously performed, so that the working gas in the closed area A is efficiently ventilated and the lip The efficiency of oil supply to the seal 40 is further improved.
[0037]
Further, since the distances L ₁ and L ₂ between the introduction hole 96 and the suction hole 104 are different from each other, the working gas introduced into the closed area A and the working gas sucked from the closed area A interfere with each other. Without such a situation, the working gas in the closed area A is quickly ventilated.
In all of the above-described one embodiment and the modified examples, the introduction hole 96 and the suction hole 104 are formed in the large-diameter end portion 34. However, the introduction hole 96 and the suction hole 104 may be formed in the eccentric bush 66. Good.
[0038]
Specifically, the fourth modified example shown in FIG. 9 shows an example in which an introduction hole 96 is formed in the eccentric bush 66, and the opening end of the introduction hole 96 is also opened close to the lead end surface of the counterweight 70. are doing.
The introduction hole 96 of the eccentric bush 66 introduces a working gas into the above-described closed area B, and supplies lubricating oil to the outer periphery of the tip of the crank pin 68.
[0039]
In addition, the large-diameter end portion 34 or the eccentric bush 66 can have only the suction hole 104. In this case, in order to sufficiently exert the function of the suction hole 104, as described above, the needle bearings 36 and 64 must be of the open type. Rolling bearings are preferred. In other words, the working gas can positively flow into the closed area A or B through the needle bearing 36 or 64 in accordance with the suction action of the working gas by the suction hole 104.
[0040]
Further, the introduction hole 96 and the suction hole 104 may be provided in both the large-diameter end portion 34 and the eccentric bush 66, respectively.
[0041]
【The invention's effect】
As described above, according to the scroll-type fluid machine of the present invention (claim 1), a through hole is formed in the large-diameter end of the rotating shaft or the eccentric bush, and the open end of the through hole is used as the lead end surface of the counterweight. Or, since it is opened close to the end face of the tail, the introduction or suction of the working gas through the through hole makes it possible to forcibly supply the working gas to places where the working gas is difficult to reach, and to lubricate the places Lubricating oil can be sufficiently supplied to the parts requiring the above.
[0042]
If the through hole is an introduction hole formed at the large-diameter end portion (claim 2), it is possible to effectively supply lubricating oil to the shaft sealing unit of the rotating shaft. In addition, in this case, if a curved portion (claim 3) or an inclined portion (claim 4) is provided on the lead end surface, the efficiency of introducing the working gas into the introduction hole can be further improved.
In addition, a suction hole is further formed at the large-diameter end in addition to the introduction hole (Claim 5). If the positions of the introduction hole and the suction hole are different from each other in the radial direction of the large-diameter end (Claim 5). Item 6), the working gas introduction efficiency through the introduction hole is further improved, and a sufficient refueling effect can be obtained.
[0043]
When the bearing of the large-diameter end or the eccentric bush is an open rolling bearing (claim 7), even if only the suction hole is formed in the large-diameter end or the eccentric bush, the desired lubrication effect can be obtained. Obtainable.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a refrigeration circuit of an automotive air conditioning system.
FIG. 2 is a vertical sectional view of the scroll compressor of FIG.
FIG. 3 is a perspective view showing a part of the compressor of FIG. 2;
FIG. 4 is a diagram showing a first modification.
FIG. 5 is a diagram showing a second modification.
FIG. 6 is a sectional view showing a part of FIG. 5;
FIG. 7 is a diagram showing a third modification.
FIG. 8 is a sectional view showing a part of FIG. 7;
FIG. 9 is a diagram showing a fourth modification.
[Explanation of symbols]
Reference Signs List 20 housing 30 rotation shaft 32 small-diameter shaft portion 34 large-diameter end portion 40 lip seal (shaft sealing unit)
52 Scroll unit 54 Movable scroll 56 Fixed scroll 66 Eccentric bush 68 Crank pin 70 Counter weight 90 Lead end surface 92 Tail end surface 96 Introducing hole (through hole)
100 Bent portion 102 Inclined portion 104 Suction hole (through hole)

Claims (7)

A housing,
The small-diameter shaft portion and the large-diameter portion extend inside the housing and have a small-diameter shaft portion on one end side and a crankpin on the other end. A supported rotation axis,
A shaft sealing unit provided on the small-diameter shaft portion of the rotating shaft, for hermetically sealing the small-diameter shaft portion between the bearings with respect to the housing;
While being housed in the housing and driven by the crank pin of the rotating shaft to perform a series of processes of suction, compression and discharge of the working gas containing the mist-like lubricating oil, a part of the working gas is A scroll unit for filling the housing.
The scroll unit,
An eccentric bush rotatably provided on the crank pin and opposed to the large-diameter end of the rotating shaft at a distance from the large-diameter end;
A movable scroll supported by the eccentric bush via an eccentric bearing, orbiting with the eccentric bush, and performing the series of processes in cooperation with a fixed scroll;
A counterweight attached to the eccentric bush and orbiting with the orbiting scroll to secure a balance with the orbiting scroll. The counterweight is positioned between the large-diameter end of the rotating shaft and the eccentric bush. A counterweight extending the large diameter end and the eccentric bush in the radial direction, having a lead end face on the leading side and a tail end face on the trailing side with respect to the turning direction of the counterweight,
A scroll hole provided in one of the large-diameter end portion and the eccentric bush, and penetrating in the axial direction and having an open end close to one of the lead surface and the tail surface. Fluid machinery. 2. The scroll-type fluid machine according to claim 1, wherein the through-hole is an introduction hole provided at the large-diameter end and having an open end close to the lead surface. 3. The scroll type fluid machine according to claim 2, wherein the lead end surface has a curved portion extending along a peripheral edge of the opening end. The scroll type fluid machine according to claim 2, wherein the lead end surface has an inclined portion that protrudes toward the opening end. The scroll-type fluid machine according to claim 2, wherein the through-hole further includes a suction hole provided at the large-diameter end and having an open end close to the tail surface. The scroll type fluid machine according to claim 5, wherein the introduction hole is located farther from the axis of the large diameter end than the suction hole. The bearing between the large-diameter end portion and the housing is an open-type rolling bearing that allows the flow of the working gas,
The scroll-type fluid machine according to claim 1, wherein the through-hole is a suction hole provided at the large-diameter end and having an open end close to the tail surface.

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