WO2017057159A1

WO2017057159A1 - Scroll-type compressor

Info

Publication number: WO2017057159A1
Application number: PCT/JP2016/077915
Authority: WO
Inventors: 裕展出口
Original assignee: 株式会社ヴァレオジャパン
Priority date: 2015-09-28
Filing date: 2016-09-22
Publication date: 2017-04-06

Abstract

[Problem] To provide a scroll-type compressor with which degradation of bearing durability can be prevented while avoiding cost increase. A scroll-type compressor 1 is provided with: a fixed scroll member 21; a revolving scroll member 22; a drive shaft 12 for transmitting rotational power; an eccentric shaft 17 provided in a position that is misaligned from the axial center of the drive shaft 12; a radial bearing 24; and a bushing 23 provided with an insertion hole 23a into which the eccentric shaft 17 is inserted, the bushing 23 being fitted over the eccentric shaft 17 via the insertion hole 23a, and supported so as to be capable of rotating relative to the radial bearing 24 and the eccentric shaft 17. Formed in one axial-direction end of the drive shaft 12 is a fitting hole 12a that fits with the eccentric shaft 17, the eccentric shaft 17 and fitting hole 12a being fitted together with a loose fitting.　

Description

Scroll compressor

The present invention relates to a scroll compressor, and more particularly to a structure of a revolution mechanism for revolving a movable scroll.

In the scroll compressor, an eccentric shaft constituting a revolving mechanism for revolving the movable scroll is engaged with a drive shaft and a bush.
The engagement between the eccentric shaft and the drive shaft is generally performed by press-fitting the eccentric shaft into a fitting hole formed in the drive shaft.

As an example of such a scroll type compressor, a rotary shaft (drive shaft) and an eccentric shaft are separately formed, and the eccentric shaft is coupled to the eccentric position of the rotary shaft by press-fitting (see FIG. Patent Document 1).

Further, there is also disclosed a structure in which a bush and an eccentric shaft are integrally formed. As such an example, a bush that transmits the eccentric rotation of the eccentric shaft to a movable scroll is provided, and the eccentric shaft is integrally formed on the bush. (See Patent Document 2).

JP 2002-371975 A JP 2002-371976 A

However, in a general scroll type compressor as described in Patent Document 1, the center of the fitting hole is at a position eccentric from the axis of the drive shaft, and therefore when the eccentric shaft is press-fitted into the fitting hole. In addition, since the force applied to the eccentric shaft in the circumferential direction is not uniform, the eccentric shaft is press-fitted with being inclined with respect to the drive shaft, or the outer peripheral surface of the drive shaft is partially expanded. There's a problem.

When the eccentric shaft is tilted and press-fitted, the bush is also tilted, and the bearing into which the bush is inserted and the outer peripheral surface of the bush do not contact evenly.
In addition, when the outer peripheral surface of the drive shaft is partially deformed, the bearing that supports the drive shaft and the outer peripheral surface of the drive shaft do not contact evenly.
In such a state, there is a problem that the dynamic load applied to the bearing becomes large and affects the durability of the bearing.

In order to solve these problems, after the eccentric shaft is press-fitted into the drive shaft, it is necessary to perform finishing processing such as cutting and polishing on the eccentric shaft and the outer peripheral surface of the drive shaft.
However, these finishing processes increase the manufacturing process and increase the cost.

In order to solve these problems, it is conceivable to integrally form the drive shaft and the eccentric shaft, but since the hardness required for the eccentric shaft must be high, an expensive material is required, and both members are If the same material is used, the cost increases.

Further, as described in Patent Document 2, in the scroll compressor in which the eccentric shaft is formed integrally with the bush, the eccentric shaft needs to have a high hardness. There is a problem of getting higher.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a scroll compressor capable of preventing deterioration of the durability of the bearing while avoiding an increase in manufacturing process and cost. .

In order to achieve the above object, a scroll compressor according to the present invention includes an end plate and a fixed scroll member having a spiral wall erected from the end plate, the movement of which is restricted at least in the radial direction with respect to the housing. The orbiting scroll member having an end plate and a spiral wall erected from the end plate, a drive shaft for transmitting rotational power, and an end of the drive shaft. An eccentric shaft provided at a position shifted from the axis of the drive shaft, a radial bearing fitted in a boss formed on the back surface of the orbiting scroll member, and an insertion hole into which the eccentric shaft is inserted. And a bushing that is externally fitted to the eccentric shaft through the insertion hole and is engaged with the radial bearing and the eccentric shaft so as to be relatively rotatable. Is fitting hole that mates with the eccentric shaft is formed at one end of the axial direction, the eccentric shaft and the fitting hole is characterized in that is fitted with clearance fit.

Since the eccentric shaft and the fitting hole are fitted by clearance fitting, no load is applied to the fitting hole due to press-fitting of the eccentric shaft, so that the eccentric shaft can be prevented from tilting and the drive shaft being deformed. it can. Accordingly, machining on the outer peripheral surface of the eccentric shaft and the drive shaft is not necessary.

In the invention of claim 2, the bush or the eccentric shaft is provided with movement restricting means for restricting the eccentric shaft from moving in the axial direction.
Since the eccentric shaft and the fitting hole are fitted by clearance fitting, it is assumed that the eccentric shaft moves in the axial direction, but with such a configuration, the eccentric shaft moves. It is possible to prevent contact with the orbiting scroll.

More specifically, the movement restricting means is constituted by a bottom portion provided in the insertion hole of the bush.
According to a fourth aspect of the present invention, the total clearance of the axial clearance between the eccentric shaft and the bottom and the axial clearance between the eccentric shaft and the bottom surface of the fitting hole is the sum of the bush and the drive shaft. And the clearance formed between the end faces facing each other in the axial direction.

By making the sum of the axial clearance between the eccentric shaft and the bottom and the axial clearance between the eccentric shaft and the bottom surface of the fitting hole larger than the clearance between the bush and the drive shaft, the axial direction of the eccentric shaft It is possible to prevent the load of.

In the invention of claim 5, the movement restricting means is constituted by a flange portion provided between the bush of the eccentric shaft and the drive shaft.
In such a configuration, the movement of the eccentric shaft is restricted by the flange portion, and the eccentric shaft can be prevented from contacting the orbiting scroll.
Further, by allowing the end face of the flange portion and the end face of the drive shaft to come into contact with each other, the load that the inner peripheral surface of the fitting hole receives from the eccentric shaft is dispersed, and wear can be reduced. .

In the invention of claim 6, the fitting hole is provided with a relief portion that avoids contact with the outer peripheral surface of the eccentric shaft, and the inner diameter surface of the opening edge portion of the fitting hole is enlarged in the circumferential direction. And it is formed in a concave shape.

By providing the relief portion on the end surface of the mating hole, it is possible to prevent wear caused by the contact between the eccentric shaft slightly inclined by the clearance fitting and the edge portion of the opening edge of the fitting hole.
In addition, when a gas containing oil flows into the fitting hole from the escape portion, an oil pool can be formed inside the fitting hole, thereby providing a lubricating effect.

According to the seventh aspect of the present invention, the fitting hole is provided with a protrusion projecting radially inward from the inner peripheral surface, and the outer peripheral surface of the eccentric shaft is brought into contact with the tip of the protrusion and the side surface of the fitting hole. It comes to touch.

Since the outer peripheral surface (side surface) of the eccentric shaft comes into contact with the tip of the protrusion and the side surface of the fitting hole, it is possible to prevent the eccentric shaft from tilting even when the gap is fitted.

In the invention of claim 8, the fitting hole may be hardened.
By performing the hardening process on the mating hole, it is possible to reduce the wear of the fitting hole.

As described above, according to the present invention, the eccentric shaft and the fitting hole can be fitted by clearance fitting to prevent the eccentric shaft from tilting and the drive shaft from being deformed. The bearing comes into contact evenly. Further, the finishing process for the outer peripheral surface of the eccentric shaft and the drive shaft is not necessary. Therefore, it is possible to prevent deterioration of the durability of the bearing while avoiding an increase in manufacturing process and cost.
Moreover, since it is not necessary to form an eccentric shaft integrally with other members, an increase in cost can be avoided.

FIG. 1 is a cross-sectional view showing an example of the overall structure of a scroll compressor according to the present invention. FIG. 2 shows a scroll compressor according to the present invention, in which a bush is externally fitted to an eccentric shaft provided at an end of a drive shaft, and this bush is engaged with a radial bearing provided at a boss portion of an orbiting scroll member. It is sectional drawing of Example 1 which shows the state made to do. FIG. 3 is a cross-sectional view showing another example of the overall structure of the scroll compressor according to the present invention, and shows an example in which a passage connecting the fitting hole and the suction passage is provided inside the drive shaft. . FIG. 4 shows a scroll compressor according to the present invention, in which a bush is externally fitted to an eccentric shaft provided at an end of a drive shaft, and this bush is engaged with a radial bearing provided at a boss portion of the orbiting scroll member. It is sectional drawing of Example 2 which shows the state made to do. FIG. 5 shows a scroll compressor according to the present invention, in which a bush is externally fitted to an eccentric shaft provided at an end portion of a drive shaft, and this bush is engaged with a radial bearing provided at a boss portion of an orbiting scroll member. It is sectional drawing of Example 3 which shows the state made to do. FIG. 6 shows a scroll compressor according to the present invention, in which a bush is externally fitted to an eccentric shaft provided at an end of a drive shaft, and this bush is engaged with a radial bearing provided at a boss portion of the orbiting scroll member. It is sectional drawing of Example 4 which shows the state made to do. FIG. 7 shows a scroll compressor according to the present invention, in which a bush is externally fitted to an eccentric shaft provided at an end portion of a drive shaft, and this bush is engaged with a radial bearing provided at a boss portion of an orbiting scroll member. It is sectional drawing of Example 5 which shows the state made to do.

Hereinafter, the scroll compressor according to the present invention will be described with reference to the drawings.

In FIG. 1, a scroll compressor 1 is an electric compressor suitable for a refrigeration cycle using a refrigerant as a working fluid, and a compression mechanism 3 is arranged on the left side in the figure in a housing 2 made of an aluminum alloy. In addition, an electric motor 4 for driving the compression mechanism 3 is disposed on the right side in the drawing. In FIG. 1, the right side in the drawing is the front of the scroll compressor 1, and the left side in the drawing is the rear of the compressor.

The housing 2 includes a compression mechanism housing member 2 a that houses the compression mechanism 3, an electric motor housing member 2 b that houses the electric motor 4 that drives the compression mechanism 3, and an inverter that houses an inverter device (not shown) that drives and controls the electric motor 4. The housing member 2c is positioned with the positioning pins 7 and fastened in the axial direction with the fastening bolts 8.

A partition wall 10 formed integrally with a shaft support portion 9a is provided on the side of the motor housing housing member 2b that faces the compression mechanism housing housing member 2a, and is opposed to the motor housing housing member 2b of the inverter housing housing member 2c. A partition wall 11 in which a shaft support portion 9b is integrally formed is provided on the side to be supported, and a drive shaft 12 is rotatably supported by the shaft support portions 9a and 9b of the

partition walls

10 and 11 via

bearings

13 and 14, respectively. Yes. The

partition wall

10, 11 formed in the motor housing housing member 2 b and the inverter housing housing member 2 c, the compression mechanism housing portion 15 a for housing the compression mechanism 3 from behind in the housing 2, and the motor for housing the motor 4. It is partitioned into a housing portion 15b and an inverter housing portion 15c that houses the inverter device.
In this example, the inverter accommodating portion 15c is defined by fixing the lid body 16 to the inverter accommodating housing member 2c with a bolt or the like (not shown).

The compression mechanism 3 is of a scroll type having a fixed scroll member 21 and an orbiting scroll member 22 disposed to face the fixed scroll member 21, and the fixed scroll member 21 is allowed to move in the axial direction with respect to the housing 2. The movement in the radial direction is restricted by the positioning pin 28, a disc-shaped end plate 21a, and a cylinder that is provided over the entire periphery along the outer edge of the end plate 21a and is erected forward. An outer peripheral wall 21b and a spiral spiral wall 21c extending forward from the end plate 21a inside the outer peripheral wall 21b.

The orbiting scroll member 22 is composed of a disc-shaped end plate 22a and a spiral spiral wall 22c erected rearward from the end plate 22a, and is erected on the back surface of the end plate 22a. An eccentric shaft 17 provided at the rear end portion of the drive shaft 12 and eccentric with respect to the axis of the drive shaft 12 is engaged with the boss portion 22 b via a bush 23 and a radial bearing 24. The bush 23 engages with the eccentric shaft 17 and the radial bearing 24 so as to be relatively rotatable, and the orbiting scroll member 22 is provided so as to be capable of revolving around the axis of the drive shaft 12.
In this embodiment, the radial bearing 24 and the boss portion 22b of the orbiting scroll member 22, and the outer peripheral surfaces of the radial bearing 24 and the bush 23 are engaged by clearance fitting.
In this embodiment, the radial bearing 24 is an inner / outer ring integrated ball bearing, but is not limited thereto, and may be an outer ring integrated needle bearing or a sliding bearing.

The fixed scroll member 21 and the orbiting scroll member 22 are meshed with each other with their

respective spiral walls

21c and 22c. A compression chamber 25 is defined in a space surrounded by the wall 22c.

Further, a thin plate-shaped annular thrust trace 26 is sandwiched between the outer peripheral wall 21 b of the fixed scroll member 21 and the partition wall 10, and the fixed scroll member 21 and the partition wall 10 are interposed via the thrust trace 26. It is faced.

The thrust trace 26 is formed of a material having excellent wear resistance, and a central hole through which a boss portion 22b of the orbiting scroll member 22 and an Oldham ring 27 described later are inserted is formed in the center. The fixed scroll member 21, the thrust trace 26, and the motor housing housing member 2 b are defined in the radial direction by positioning pins 28 that are inserted into pin insertion holes formed in the thrust trace 26.

The shaft support portion 9a formed integrally with the partition wall 10 of the electric motor housing member 2b has a through hole in the center, and the inner surface thereof is formed in a stepwise manner toward the thrust trace 26, From the front side farthest from the thrust trace 26, the bearing housing 31 in which the bearing 13 is housed, is integrally formed with the bush 23, or is externally fitted to the bush so as not to rotate relative to the bush 23. A weight accommodating portion that accommodates a balance weight 32 that rotates with the rotation of the drive shaft 12 (in this example, the balance weight 32 is formed separately from the bush 23 and is fitted on the bush 23 so as not to rotate relative to the bush 23). 33, formed following the weight accommodating portion 33, and prevents the orbiting scroll member 22 from rotating with the orbiting scroll member 22. Oldham Oldham accommodating portion 34 for accommodating the ring 27 is formed that.

Therefore, the orbiting scroll member 22 is rotated by the rotation of the drive shaft 12, but revolves around the axis of the drive shaft 12 while the rotation is restricted by the Oldham ring 27.
The mechanism for preventing rotation is not limited to the Oldham ring, but may be a pin-hole, pin-ring, pin-link, or the like.

Suction for sucking refrigerant gas introduced from a suction port 40 (described later) through a suction path 45 between the outer peripheral wall 21b of the fixed scroll member 21 and the outermost peripheral portion of the spiral wall 22c of the orbiting scroll member 22. A chamber 35 is formed, and the refrigerant gas compressed in the compression chamber 25 is discharged through a discharge hole 36 formed substantially at the center of the fixed scroll member 21 behind the fixed scroll member 21 in the housing. A discharge chamber 37 is defined between the rear end wall of the compression mechanism housing member 2a. The refrigerant gas discharged into the discharge chamber 37 is pumped to an external refrigerant circuit through the discharge port 38.

On the other hand, a stator 41 and a rotor 42 constituting the electric motor 4 are provided in the electric motor accommodating portion 15b formed in the front part of the partition wall 10 in the housing 2. The stator 41 includes a cylindrical iron core 43 and a coil 44 wound around the iron core 43, and is fixed to the inner surface of the housing 2 (electric motor housing member 2b). The drive shaft 12 is fixedly mounted with a rotor 42 made of a magnet rotatably accommodated inside the stator 41, and the rotor 42 is rotated by a rotating magnetic force formed by the stator 41. It is designed to rotate. The stator 41 and the rotor 42 constitute an electric motor 4 composed of a brushless DC motor.

A suction port 40 for sucking refrigerant gas into the motor housing portion 15b is formed on the side surface of the housing 2 (motor housing housing member 2b), and a gap between the stator 41 and the housing 2 (motor housing housing member 2b). In addition, the refrigerant gas that has flowed from the suction port 40 into the motor housing portion 15b through the holes formed in the partition wall 10 and the gap formed between the fixed scroll member 21 and the housing 2 is supplied to the suction chamber 35. A leading suction path 45 is configured.

The inverter device housed in the inverter housing member 2c is electrically connected to the stator 41 via a terminal (airtight terminal) 60 attached to a through hole 61 formed in the partition wall 11, and is connected to the motor 4. Power is supplied from the inverter device.

Therefore, when the rotor 42 rotates and the drive shaft 12 rotates by supplying power to the electric motor 4, the orbiting scroll member 22 is driven via the eccentric shaft 17 and the bush 23 in the compression mechanism 3. At this time, since the orbiting scroll member 22 is prevented from rotating by the rotation preventing mechanism including the Oldham ring 27, only the revolving motion is allowed with respect to the fixed scroll member 21.

Due to the revolving motion of the orbiting scroll member 22, the compression chamber 25 moves while gradually reducing the volume from the outer peripheral side of the

scroll walls

21c, 22c of both scroll members to the center side, so that the suction chamber 35 sucks into the compression chamber 25. The compressed refrigerant gas is compressed, and the compressed refrigerant gas is discharged into the discharge chamber 37 through the discharge hole 36 formed in the end plate 21 a of the fixed scroll member 21. Then, it is sent to the external refrigerant circuit through the discharge port 38.

In the above configuration, the bush 23 shown in FIG. 2 has a cylindrical shape, and has an insertion hole 23a that extends in the axial direction and can be inserted into the eccentric shaft 17 at a position shifted in the radial direction from the axial center. A weight fitting margin 23c for reducing the outer diameter and fitting the balance weight 32 is formed on the periphery of the end of the motor.
Note that the inner diameter of the insertion hole 23 a is slightly larger than the outer diameter of the eccentric shaft 17.

Moreover, the front side (right side in the figure) end surface of the inner peripheral member of the radial bearing 24 can come into contact with the stepped portion provided on the bush 23, and further, the rear side (left side in the figure) of the outer peripheral member of the radial bearing 24 The end surface is configured to be able to come into contact with a stepped portion provided on the boss portion 22 b of the orbiting scroll member 22. With this configuration, the axial movement of the bush 23 is restricted, and the bush 23 is prevented from coming into contact with the orbiting scroll member 22.

The balance weight 32 includes a fitting portion 32a formed in an annular shape, and a fan-shaped weight main body 32b integrally formed over a predetermined angular range on the periphery of the fitting portion 32a. The portion 32 a is fitted on the outer periphery of the weight fitting allowance 23 c of the bush 23 by, for example, press fitting, and rotates together with the bush 23.

The balance weight 32 extends so as to approach the orbiting scroll member 22 and also extends in a direction away from the orbiting scroll member 22, thereby reducing the radial dimension, The required mass is ensured while avoiding interference.

One end side of the eccentric shaft 17 is inserted into an insertion hole 23 a formed in the bush 23, and the other end side is fitted into a fitting hole 12 a formed on the end surface of the drive shaft 12 facing the orbiting scroll member 22. Yes.

The inner diameter of the fitting hole 12a is slightly larger than the outer diameter of the eccentric shaft 17 (for example, the difference between the inner diameter and the outer diameter of these members is about 20 micrometers).
Therefore, the eccentric shaft 17 and the fitting hole 12a are fitted by gap fitting.

As described above, according to the present embodiment, the eccentric shaft 17 and the fitting hole 12a can be fitted by clearance fitting to prevent the eccentric shaft 17 from tilting and the drive shaft 12 from being deformed. The bearing (radial bearing 24) or the drive shaft 12 and the

bearings

13 and 14 come into contact with each other evenly. Further, the finishing process for the outer peripheral surfaces of the eccentric shaft 17 and the drive shaft 12 is not necessary. Therefore, it is possible to prevent deterioration of the durability of the bearing while avoiding an increase in manufacturing process and cost.

Note that the scroll compressor 1 of the present invention may be configured such that the orbiting scroll member 22 is pressed against the fixed scroll member 21 by the back pressure of the scroll compressor 1.

Specifically, as shown in FIG. 3, the weight accommodating portion is compressed from the compression chamber 25 so that a force is applied to the orbiting scroll member 22 toward the fixed scroll member 21 by the pressure of the refrigerant gas introduced into the weight accommodating portion 33. A passage (not shown) for the refrigerant gas leading to 33 is provided, and a passage 12b connecting the fitting hole 12a and the motor housing portion 15b for returning the refrigerant gas introduced into the weight housing portion 33 to the suction passage 45. Is provided inside the drive shaft 12.

In such a configuration, since the refrigerant gas containing oil flows into the fitting hole 12a, it is possible to prevent the inner peripheral surface of the fitting hole 12a from being worn.
Further, in order to return the refrigerant gas to the suction path 45, it is necessary to provide a throttle. However, by using the gap formed between the fitting hole 12a and the eccentric shaft 17 as a refrigerant gas passage, Thus, it is possible to configure without newly providing a diaphragm.

Furthermore, in the process in which the refrigerant gas is introduced into the suction passage 45, it is possible to lubricate the bearing 14 provided in the motor housing 15b.

Note that the bush may be configured so as to restrict the axial movement of the eccentric shaft 17 and to prevent an axial load from being applied to the eccentric shaft 17.

Specifically, as shown in FIG. 4, the bush 23 includes a bottom 23 d as movement restriction means for restricting movement of the eccentric shaft 17 in the axial direction.
The bottom 23d is provided in the insertion hole 23a of the bush 23, and is formed so as to narrow its inner diameter from the end surface (edge surface) facing the orbiting scroll member 22 toward the inner side in the radial direction. A through hole 23e communicating with the insertion hole 23a is formed.

Here, the total clearance A1 between the axial clearance A1 between the eccentric shaft 17 and the bottom 23d and the axial clearance A2 between the eccentric shaft and the bottom surface of the fitting hole is the axial direction between the bush 23 and the drive shaft 12. The clearance B is formed larger than the clearance B formed between the end faces facing each other.

When an axial load is applied to the eccentric shaft 17 by the bottom portion 23d and the bottom surface of the fitting hole 12a, the eccentric shaft 17 may be inclined and the eccentric shaft 17 may strongly hit the opening edge of the fitting hole 12a. Concerned.
However, the clearance A is set larger than the clearance B, so that no axial load is applied to the eccentric shaft 17 and the wear of the member can be reduced.

Further, the fitting hole 12a may be prevented from being worn by restricting the axial movement of the bush 23 and further dispersing the force transmitted from the eccentric shaft 17 to the drive shaft.

Specifically, as shown in FIG. 5, the eccentric shaft 17 serves as a movement restricting means, and is a flange portion 17 b formed to project outward in the radial direction at an intermediate portion formed between one end and the other end. It is comprised.

The flange portion 17b is formed in a disk shape having a diameter larger than the inner diameter of the fitting hole 12a.
The end face of the flange portion 17b and the end face of the drive shaft 12 facing each other are provided so as to be in contact with each other.

As described above, the axial movement of the eccentric shaft 17 is restricted by the flange portion 17b, and the eccentric shaft 17 can be prevented from contacting the orbiting scroll member 22. Further, the end face of the flange portion 17b and the end face of the drive shaft 12 are in contact with each other, so that the load received by the drive shaft 12, that is, the load applied to the fitting hole 12a can be dispersed, thereby preventing wear. be able to.

In the above-described embodiment, the inner diameter of the fitting hole 12a is slightly larger than the outer diameter of the eccentric shaft 17, so that a slight gap (clearance) is generated between the eccentric shaft 17 and the fitting hole 12a. There is a possibility that the eccentric shaft 17 is slightly inclined.

If the scroll compressor 1 is operated in such a state, the outer peripheral surface of the drive shaft 12 and the opening edge of the fitting hole 12a may be rubbed and worn.
Therefore, in order to prevent wear of these

members

17 and 12a, the fitting hole 12a may be configured to avoid contact with the outer peripheral surface of the eccentric shaft 17.

Specifically, as shown in FIG. 6, the opening edge portion of the fitting hole 12a is provided with a relief portion 12c formed in a concave shape to avoid contact with the outer peripheral surface of the eccentric shaft 17.

The escape portion 12c is formed in a concave shape by expanding the inner peripheral surface in the vicinity of the opening edge of the fitting hole 12a in the circumferential direction.
If the depth in the radial direction of the escape portion 12c is too shallow, the eccentric shaft 17 comes into contact with the peripheral edge of the fitting hole 12a. Therefore, depending on the difference between the inner diameter of the fitting hole 12a and the outer diameter of the eccentric shaft 17. It is formed.
That is, the depth in the radial direction is set according to the inclination of the eccentric shaft 17 so as to avoid the eccentric shaft 17 from contacting the opening edge portion of the fitting hole 12a.

As described above, the escape portion 12c is provided on the end face of the fitting hole 12a, thereby preventing the outer peripheral surface of the slightly inclined eccentric shaft 17 from coming into contact with the opening edge of the fitting hole 12a and being worn. Is possible.

Further, as described in the above embodiment, the scroll compressor of the present invention is configured so that the orbiting scroll member 22 is pressed against the fixed scroll member 21 by the back pressure of the scroll compressor 1 in this embodiment as well. Also good.

In this case, when the refrigerant gas flows into the fitting hole 12a from the escape portion 12c, the oil pool can be accumulated in the fitting hole 12a, so that a further lubrication effect can be given. Wear can be reduced.

In the above-described embodiment, since the clearance is fitted, the eccentric shaft 17 may be inclined with respect to the fitting hole 12a. However, the eccentric shaft 17 extends along the inner peripheral surface of the fitting hole 12a. May be provided.

Specifically, as shown in FIG. 7, two through holes 12 c communicating with the fitting holes 12 a are formed on the outer peripheral surface of the drive shaft 12, and set screws 18 serving as protrusions are respectively formed in the through holes 12 c. Is provided.

A thread groove is formed on the inner peripheral surface of the through hole 12c.
The set screw 18 is screwed into this thread groove, and protrudes from the through hole 12c toward the wall surface of the fitting hole 12a facing so that the tip abuts against the side surface of the eccentric shaft 17. It has been.

Therefore, the side surface of the eccentric shaft 17 comes into contact with both the front end of the set screw 18 and the side surface of the fitting hole 12a by being pressed (contacted) with the front end of the set screw 18. For this reason, since it can prevent that the eccentric shaft 17 inclines with respect to the fitting hole 12a, it becomes possible to prevent the drive shaft 12 from wearing.
The protrusions are not limited to set screws, but may be formed by press-fitting pins or caulking.

Further, the fitting hole may be cured.
Wearing of the fitting hole 12a can be prevented by subjecting the inner peripheral surface of the fitting hole 12a to a hardening process such as plating and quenching.

DESCRIPTION OF SYMBOLS 1 Scroll type compressor 12 Drive shaft

12a Fitting hole

12c Escape part 17 Eccentric shaft 17b Flange part 18 Set screw (projection)
2 Housing 21 Fixed scroll member 21a End plate (fixed scroll member)
21c spiral wall (fixed scroll member)
22 orbiting scroll member 22a end plate (orbiting scroll member)
22c spiral wall (orbiting scroll member)
23 bush 23a insertion hole 23d bottom 24 radial bearing 32 balance weight,

Claims

A movement of at least the radial direction with respect to the housing is restricted, a fixed scroll member having an end plate and a spiral wall standing from the end plate, and a fixed scroll member disposed opposite to the fixed scroll member, An orbiting scroll member having a spiral wall provided, a drive shaft for transmitting rotational power, an eccentric shaft provided at an end of the drive shaft and deviated from the axis of the drive shaft; A radial bearing internally fitted in a boss formed on the back surface of the orbiting scroll member, and an insertion hole into which the eccentric shaft is inserted. The radial shaft is externally fitted to the eccentric shaft through the insertion hole and the radial A scroll compressor comprising a bearing and a bush engaged with the eccentric shaft in a relatively rotatable manner,
In the drive shaft, a fitting hole for fitting with the eccentric shaft is formed at one end in the axial direction,
The scroll type compressor, wherein the eccentric shaft and the fitting hole are fitted by gap fitting.
The scroll compressor according to claim 1, wherein a movement restricting means for restricting the eccentric shaft from moving in the axial direction is provided on the bush or the eccentric shaft.
3. The scroll compressor according to claim 2, wherein the movement restricting means is a bottom portion provided in an insertion hole of the bush.
The total clearance of the axial clearance between the eccentric shaft and the bottom portion and the axial clearance between the eccentric shaft and the bottom surface of the fitting hole is opposite to each other in the axial direction of the bush and the drive shaft. The scroll compressor according to claim 3, wherein the scroll compressor is larger than a clearance formed between the end faces.
3. The scroll compressor according to claim 2, wherein the movement restricting means is a flange portion provided between the bush of the eccentric shaft and the drive shaft.
The fitting hole has an escape portion that avoids contact with the outer peripheral surface of the eccentric shaft,
The scroll-type compression according to any one of claims 1 to 5, wherein the escape portion is formed in a concave shape by expanding an inner peripheral surface of an opening edge portion of the fitting hole in a circumferential direction. Machine.
The fitting hole is provided with a protrusion that protrudes radially inward from the inner peripheral surface,
The scroll compressor according to any one of claims 1 to 6, wherein an outer peripheral surface of the eccentric shaft is in contact with a tip of the protrusion and a side surface of the fitting hole.
The scroll compressor according to any one of claims 1 to 7, wherein the fitting hole is subjected to a curing process.