JP2000045971A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain lubrication of a pivot bearing for a long period of time with grease so as to extend the life of a pivot bearing even when cylindrical rollers and the like are used as the pivot bearing. SOLUTION: A pivot bearing 11 for pivotably supporting a pivot scroll 5 with respect to a crank pin of a drive shaft 3 is provided inside a boss portion 10A of a pivot scroll 5. Further, a grease reservoir 12 is provided on the crank pin of the drive shaft 3, and the grease reservoir 12 is filled with grease for lubricating the pivot bearing 11. This grease is supplied to the pivot bearing 11 side when its viscosity is decreased as the temperature of the pivot bearing 11 rises during compression.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type fluid machine suitable for use in an air compressor, a vacuum pump and the like.
In particular, the present invention relates to an oilless scroll fluid machine.

[0002]

2. Description of the Related Art Generally, a scroll-type fluid machine is provided with a casing, a fixed scroll provided in the casing and having a spiral wrap portion provided on a head plate, and a rotatable member provided on the casing and having a tip end side. A drive shaft that has become a crank, and a spiral wrap portion that is rotatably provided on the crank of the drive shaft and that overlaps the wrap portion of the fixed scroll and that defines a plurality of compression chambers are provided upright on the front side of the head plate. And a revolving scroll.

[0003] In this type of scroll type fluid machine according to the prior art, a drive shaft is rotationally driven from the outside, and the orbiting scroll is orbited with a fixed eccentricity with respect to the fixed scroll. While sucking a fluid such as air from the suction port, the fluid is sequentially compressed in each compression chamber between the wrap portion of the fixed scroll and the wrap portion of the orbiting scroll, and compressed from the discharge port provided at the center of the fixed scroll. Discharge the fluid to the outside.

Further, in this prior art, a boss is provided on the rear side of the end plate of the orbiting scroll, and a turning bearing for supporting the orbiting scroll so as to be able to turn with respect to the crank of the drive shaft is provided in the boss. . The inside of the slewing bearing is filled with grease to enhance lubrication of the slewing bearing.

[0005]

In the above-mentioned conventional scroll type fluid machine, a needle bearing, a cylindrical roller and the like are generally used as a turning bearing in order to reduce the size and weight of the entire apparatus.

[0006] However, such a slewing bearing such as a needle bearing has a relatively small total volume of a space (gap) secured inside (hereinafter referred to as an internal space volume).
This slewing bearing can only be filled with a small amount of grease. As a result, there is a problem that the grease filled in the slewing bearing is easily depleted, which causes damage to the slewing bearing.

Further, if the slewing bearing itself is filled with an excessive amount of grease, the stirring resistance when the grease is stirred inside the slewing bearing is increased, which causes a problem that the performance of the slewing bearing is reduced. .

The present invention has been made in view of the above-mentioned problems of the prior art. Even when a cylindrical roller or the like is used as a slewing bearing, the slewing bearing can be lubricated with grease for a long period of time. It is an object of the present invention to provide a scroll-type fluid machine capable of extending the life and improving the reliability of the device.

[0009]

In order to solve the above-mentioned problems, a scroll-type fluid machine according to the present invention comprises a casing, a fixed scroll provided in the casing, and a spiral wrap portion standing upright on a head plate. A drive shaft having a base end rotatably provided in the casing and a distal end serving as a crank, and a spiral wrap defining a plurality of compression chambers overlapping the wrap portion of the fixed scroll on the surface side of the head plate. And an orbiting scroll provided with a boss on the back side of the end plate, and a orbit provided on the boss of the orbiting scroll and supporting the orbiting scroll so as to be rotatable with respect to the crank of the drive shaft. Bearings.

A feature of the structure adopted in the first aspect of the present invention is that a grease reservoir for lubricating a swing bearing is provided on a crank of a drive shaft.

With this configuration, the temperature of the slewing bearing increases during the compression operation, and the heat from the slewing bearing is transmitted to the grease reservoir, so that the grease filled in the grease reservoir has a reduced viscosity. Thus, grease can be supplied from the grease reservoir to the orbiting bearing provided in the boss of the orbiting scroll.

According to the second aspect of the present invention, the drive shaft is provided with an opening for opening a grease reservoir in the boss portion, and the opening has a cross-sectional shape in the radial direction of the drive shaft which is larger than that of the grease receiving portion. Are also made smaller.

With this configuration, the grease filled in the grease reservoir can be supplied little by little to the swing bearing through the opening provided in the drive shaft.

According to the third aspect of the present invention, the opening is disposed at a position eccentric with respect to the rotation center of the drive shaft.

With this configuration, the grease in the grease reservoir can be smoothly supplied to the slewing bearing through the opening by the centrifugal force of the drive shaft.

Further, according to the invention of claim 4, an air introduction passage extending along the center of rotation in the drive shaft for introducing external air into the grease reservoir into the drive shaft and opening into the grease reservoir. Is provided.

With this configuration, since external air can be introduced into the grease reservoir through the air introduction passage, the grease in the grease reservoir can be smoothly supplied to the slewing bearing.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an oilless scroll type air compressor will be described as an example of a scroll type fluid machine according to an embodiment of the present invention with reference to the accompanying drawings.

FIG. 1 and FIG. 2 show a first embodiment of the present invention. In the drawing, reference numeral 1 denotes a casing forming an outer frame of a scroll type air compressor.
Is formed in a stepped cylindrical shape composed of a large diameter portion 1A and a small diameter portion 1B.

Reference numeral 2 denotes a fixed scroll fixed to the large-diameter portion 1A of the casing 1. The fixed scroll 2 is a disk arranged so that the center thereof coincides with an axis O1-O1 of a drive shaft 3 described later. End plate 2A, a spiral wrap portion 2B erected on the surface of the end plate 2A, and an outer edge 2C provided radially outside the end plate 2A so as to surround the wrap portion 2B from the outside. A large number of radiating fins 2D are provided on the rear surface of the end plate 2A. The fixed scroll 2 has an outer edge 2 </ b> C integrally attached to the distal end side of the large diameter portion 1 </ b> A of the casing 1.

Reference numeral 3 denotes a drive shaft rotatably supported in the small screw portion 1B of the casing 1. The drive shaft 3 is formed of a ferrous material into a stepped column shape, and has a base end side. A pulley 13 to be described later is provided, and is driven to rotate about an axis O1-O1. A crank pin 3A protrudes from the distal end of the drive shaft 3, and the axis O2-O2 of the crank pin 3A is disposed at a position eccentric to the axis O1-O1 by a dimension δ.

The drive shaft 3 has a weight mounting portion 3B at a position where the balance weight 4 to be described later is mounted on the distal end side thereof. The weight mounting portion 3B is formed to have a larger diameter than the crank pin 3A. I have.

Reference numeral 4 denotes a balance weight fixed to the distal end side of the drive shaft 3. The balance weight 4 balances the rotation of the entire drive shaft 3 with respect to the orbiting operation of the orbiting scroll 5 described later.

Reference numeral 5 denotes an orbiting scroll provided in the casing 1 so as to be capable of orbiting in opposition to the fixed scroll 2. The orbiting scroll 5 comprises a orbiting scroll main body 6 and a back plate 10 to be described later. Numeral 5 is pivotably supported by a crank pin 3A using a pivot bearing 11 described later. The orbiting scroll main body 6 is similar to the fixed scroll 2 in that the end plate 6A and the spiral wrap 6
B, etc., and a large number of heat radiation fins 6C are provided on the end plate 6A.

The orbiting scroll 5 has a wrap portion 6
B is disposed so as to overlap with the wrap portion 2B of the fixed scroll 2 by a predetermined angle (for example, 180 degrees),
A plurality of compression chambers 7, 7, between the wrap portions 2B, 6B
... is defined. During operation of the scroll air compressor, air is sucked into the compression chamber 7 on the outer peripheral side from the suction ports 8 provided on the outer peripheral side of the fixed scroll 2 while the air is being swirled by the orbiting scroll 5. Each compression chamber 7
Then, compressed air is discharged from the center compression chamber 7 to the outside through a discharge port 9 provided at the center of the fixed scroll 2.

Reference numeral 10 denotes a back plate fixed to the tip of each of the radiation fins 6C of the orbiting scroll main body 6. A boss 10A is integrally formed at the center of the back plate 10. A boss 1 is provided on the back side of the back plate 10.
0A, a notch 10B is provided in the notch 1B.
OB constitutes a grease supply path for supplying grease in a grease reservoir 12 described later to the slewing bearing 11 side.

Numeral 11 denotes a slewing bearing provided in the boss 10A of the back plate 10. The slewing bearing 11 is constituted by, for example, a needle bearing, a cylindrical roller, etc. 3A is inserted. The orbiting bearing 11 is configured to support the orbiting scroll 5 to be able to orbit with respect to the crankpin 3 </ b> A of the drive shaft 3.

Reference numeral 12 denotes a grease reservoir provided on the crankpin 3A of the drive shaft 3. The grease reservoir 12 is formed as a bottomed circular hole at the tip of the crankpin 3A of the drive shaft 3. The grease filled in the grease reservoir 12 is supplied to the slewing bearing 11 through the notch 10B of the back plate 10 due to a decrease in viscosity during the compression operation as described later.

The grease reservoir 12 is arranged such that the inner bottom side, which is the bottom side of the hole, is located at least on the crankpin 3A side from the boundary between the crankpin 3A and the weight mounting portion 3B. With this, the crank pin 3A
The thickness of the dimension d is secured on the bottom side of the hole of the grease reservoir 12, so that the strength of the entire crankpin 3A is increased.

Reference numeral 13 denotes a pulley integrally attached to the base end of the drive shaft 3 by bolts 14 or the like.
The centrifugal fan 15 includes a fan casing 16 attached to the small diameter portion 1B of the casing 1.
Housed within.

The scroll type air compressor according to the present embodiment has the above-described configuration. Next, the operation of the scroll type air compressor will be described.

First, when the drive shaft 3 is rotated by the electric motor, the orbiting scroll 5 makes a orbital movement around the drive shaft 3 with a turning radius of the dimension δ, and the wrap portion 2B of the fixed scroll 2 and the orbiting scroll 5 Are continuously reduced between the wrap portions 6B. As a result, while the outside air sucked from the suction port 8 of the fixed school 2 is sequentially compressed in each of the compression chambers 7, this compressed air is stored in the outside air tank or the like from the discharge port 9 of the fixed scroll 2.

Here, in the present embodiment, a grease reservoir 12 is provided at the tip of the crank pin 3A of the drive shaft 3, and the grease reservoir 12 is filled with grease for lubricating the slewing bearing 11. During the above-described compression operation, the temperature of the slewing bearing 11 rises, and the slewing bearing 1
When the heat from 1 is transmitted to the grease reservoir 12, the viscosity of the grease in the grease reservoir 12 gradually decreases.
Thus, the grease can be smoothly supplied to the slewing bearing 11 in the direction indicated by the arrow in FIG.

Therefore, even when the slewing bearing 11 is constituted by a bearing having a relatively small internal space volume, such as a needle bearing or a cylindrical roller, as in the present embodiment,
During the compression operation, the slewing bearing 11 can be constantly maintained in a lubricated state by the grease in the grease reservoir 12,
The durability and life of the slewing bearing 11 can be improved, and the reliability of the device can be improved.

Further, as described in the prior art, the slewing bearing 1
It is no longer necessary to fill the grease itself with a large amount of grease more than necessary, so that the performance of the slewing bearing 11 can be prevented from deteriorating due to the agitation resistance of the grease, and the performance of the slewing bearing 11 can be enhanced.

Next, FIG. 3 shows a second embodiment of the present invention. In this embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. It shall be omitted.

However, this embodiment is characterized in that the drive shaft 2
1 has a configuration in which an air introduction path 24 for introducing air from the outside into the grease reservoir 22 is provided.

Here, the drive shaft 21 has a crank pin 21A substantially in the same manner as the drive shaft 3 described in the first embodiment.
And a weight mounting portion 21B.
The grease reservoir 22 is provided in 1A. The pulley 13 is integrally attached to a base end side of the drive shaft 21 by a bolt 23 forming a part of the drive shaft 21.

The air introduction passage 24 is formed as an axial passage extending through the drive shaft 21 and the bolt 23 in the axial direction, and an axis O 1 serving as a rotation center of the drive shaft 21.
It is arranged along -O1. One end of the air introduction passage 24 is open to the head of the bolt 23, and the other end is open to the grease reservoir 22, and guides external air into the grease reservoir 22.

Thus, also in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the first embodiment. In particular, in the present embodiment, since the external air can be guided into the grease reservoir 22 by the air introduction passage 24, the grease in the grease reservoir 22 can be more smoothly supplied to the swivel bearing 11.

Next, FIG. 4 shows a third embodiment of the present invention. In this embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and description thereof will be given. It shall be omitted.

However, this embodiment is characterized in that the drive shaft 3
The crankpin 3A is provided with a cover plate 31 which covers the opening side of the grease reservoir 12 and forms a part of the crankpin 3A, and the cover plate 31 has an opening for opening the grease reservoir 12 to the outside. The configuration is such that a small hole 32 is formed.

Here, the small hole 32 is formed in the central portion of the lid plate 31,
That is, the crank pin 3A is disposed on the axis O2-O2 of the crank pin 3A eccentric with respect to the axis O1-O1 of the drive shaft 3.
The sectional shape of the small hole 32 in the radial direction is the grease pool 1.
2 is formed smaller than the radial cross-sectional shape.

Thus, in the present embodiment having such a configuration, substantially the same operation and effect as those of the first embodiment can be obtained. In the present embodiment, grease is particularly removed from the grease reservoir 12. Slewing bearing 1 through small hole 32
One side can be supplied little by little, and the grease pool 12
The grease replenishment time and the like can be extended. Further, since the small hole 32 can be disposed at a position eccentric with respect to the axis O1-O1 of the drive shaft 3, the grease in the grease reservoir 12 is directed from the small hole 32 toward the slewing bearing 11 by the centrifugal force from the drive shaft 3. Can be supplied more smoothly.

Next, FIGS. 5 and 6 show a fourth embodiment of the present invention. In this embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals. The description is omitted.

The feature of this embodiment is that the drive shaft 3
The crank pin 3A is provided with a cover plate 41 which covers the opening side of the grease reservoir 12 and forms a part of the crank pin 3A, and the cover plate 41 has an opening for opening the grease reservoir 12 to the outside. A small hole 42 is formed as the drive shaft 3
The eccentric dimension L of the small hole 42 with respect to the axis O1 -O1 is set as large as possible.

Thus, in the present embodiment configured as described above, substantially the same operation and effect as in the third embodiment can be obtained. In the present embodiment, in particular, in the present embodiment, the axis O 1 − of the drive shaft 3 is provided. Since the eccentric dimension L of the small hole 42 with respect to O1 is set to be as large as possible, the centrifugal force from the drive shaft 3 can further act on the grease passing through the small hole 42, and the grease 12 Grease can be more smoothly supplied from the small hole 42 toward the slewing bearing 11.

Next, FIG. 7 shows a fifth embodiment of the present invention. In this embodiment, the same components as those in the above-described first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. It shall be omitted.

However, this embodiment is characterized in that the drive shaft 3
A cover plate mounting step 51 and a grease reservoir 52 are provided on the crank pin 3A. The cover plate mounting step 51 has a cover plate 53 which covers the opening side of the grease reservoir 52 and forms a part of the crank pin 3A. At the same time, a small hole 54 as an opening for opening the grease reservoir 52 to the outside is formed in the cover plate 53, and the small hole 54 is formed along the axis O1-O1 (axis O) of the drive shaft 3.
2 -O2).

Thus, also in the present embodiment configured as described above, it is possible to obtain substantially the same operation and effect as in the fourth embodiment.

Next, FIG. 8 shows a sixth embodiment of the present invention. The feature of this embodiment is that the tip of the crank pin of the drive shaft is located between the drive shaft and the orbiting scroll. A variable crank for variably adjusting the turning deformation is provided.This variable crank is provided with a grease reservoir on a fitting shaft portion fitted to the boss portion of the orbiting scroll, and the drive shaft and the variable crank are supplied with external air. The configuration is such that an air introduction path for introducing the grease into the reservoir is provided.

In the drawing, reference numeral 61 denotes a casing according to the present embodiment. The casing 61 has a large diameter portion 61A and a small diameter portion 61A.
B is formed in a stepped cylindrical shape. Reference numeral 62 denotes a fixed scroll provided on the casing 61. The fixed scroll 62 includes a head plate 62A, a wrap portion 62B provided upright on the head plate 62A, a cylindrical portion 62C provided on an outer edge of the head plate 62A, The flange 62D is provided on the outer peripheral side of the portion 62C and abuts with the small diameter portion 61B of the casing 61, and includes a large number of radiation fins 62E.

A drive shaft 63 is supported by the small diameter portion 61B of the casing 61. The drive shaft 63 has substantially the same configuration as the drive shaft 3 described in the first embodiment. A fitting hole 64 into which a variable crank 70 described later is fitted is provided.

Reference numeral 65 denotes an orbiting scroll provided rotatably in the casing 61. The orbiting scroll 65 comprises an orbiting scroll main body 66 and a back plate 68 to be described later. The orbiting scroll main body 66 has a head plate 66A and a wrap portion 66B similarly to the fixed scroll 62.
And radiating fins 66C and the like.
Define compression chambers 67, 67,... Between the wrap portion 62B of the fixed scroll 62.

Reference numeral 68 denotes a rear plate provided on the orbiting scroll main body 66, and reference numeral 69 denotes a boss 6 of the rear plate 68.
8A, the orbiting bearing 69 is configured to rotatably support the orbiting scroll 65 with respect to a variable crank 70 integrated with the drive shaft 63.

Reference numeral 70 denotes a variable crank provided on the distal end side of the drive shaft 63 instead of the crank pin 3A of the drive shaft 3 according to the first embodiment. The variable crank 70 is disclosed, for example, in Japanese Patent Application Laid-Open No. 9-147467. And constitutes a part of the drive shaft 63.

The variable crank 70 has a drive shaft 63
Fitting shaft portion 70A provided by fitting into fitting hole 64 of
And an eccentric shaft portion 70B provided to be fitted in the boss portion 68A of the orbiting scroll 65. The eccentric shaft portion 70B is arranged so that its axis is eccentric with respect to the axis of the drive shaft 63, and forms a crankpin of the drive shaft 63.

The variable crank 70 rotates together with the drive shaft 63 during the operation of the scroll air compressor, thereby orbiting the orbiting scroll 65 with a turning radius of the dimension δ. Further, the variable crank 70 receives the combined force of the pressure of the compression chamber 67 and the centrifugal force due to the rotation of the drive shaft 63, thereby rotating the wrap portion 65 </ b> B of the orbiting scroll 65 while rotating relatively to the drive shaft 63. The fixed scroll 62 is configured to be pressed against the wrap portion 62B.

Reference numeral 71 denotes a cylinder provided between the fitting hole 64 of the drive shaft 63 and the fitting shaft portion 70A of the variable crank 70.
The cylindrical body 71 is formed of a thermal expansion material such as a styrene-based thermoplastic resin, for example, and is configured to thermally expand by compression heat from the compression chamber 67 or the like. Also, this cylinder 71
Are arranged with a small gap between the fitting hole 64 and the fitting shaft portion 70A, and are configured to allow the variable crank 70 to rotate relative to the drive shaft 63 in the initial stage of the compression operation. I have.

Reference numeral 72 denotes an eccentric shaft portion 70B of the variable crank 70.
A grease reservoir 73 provided on the drive shaft 63 and an air introduction passage provided on the variable crank 70. The air introduction passage 73 extends inside the drive shaft 63 along its axis. A first passage portion 73A having an opening on the base end side and an opening on the other end side in the fitting hole 64, a crank shape extending in the variable crank 70 in the axial direction, and one end opening in the first passage portion 73A; An end side is constituted by a second passage portion 73 </ b> B opened inside the grease reservoir 72.

Reference numeral 74 denotes a suction port provided on the outer peripheral side of the fixed scroll 62, 75 denotes a discharge port provided on the center side of the fixed scroll 62, and the discharge port 75 has a discharge pipe 7.
6 are attached.

Thus, also in the present embodiment configured as described above, air from the outside can be introduced into the grease reservoir 72 by the air introduction passage 73, and the operation is substantially the same as that of the second embodiment. The effect can be obtained.

In particular, in the present embodiment, during the compression operation,
By rotating the variable crank 70 relative to the drive shaft 63, the wrap portion 66B of the orbiting scroll 65 can be pressed against the wrap portion 62B of the fixed scroll 62, so that the airtightness in the compression chamber 67 is enhanced and compression is performed. Efficiency can be increased.

When the compression operation is continuously performed while the wrap portion 66B of the orbiting scroll 65 is pressed against the wrap portion 62B of the fixed scroll 62, the wrap portion 6
The wear between 2B and 66B gradually progresses.

However, in this embodiment, when the compression operation is continuously performed, the heat generated by the compression from the compression chamber 67 causes the cylinder 71
By heating and gradually expanding the heat, the rotational position of the variable crank 70 with respect to the drive shaft 63 can be fixed, so that the progress of wear can be stopped before the wrap portions 62B and 66B reach the wear limit. The life of the wrap portions 62B and 66B can be extended.

In each of the above embodiments, a scroll type air compressor has been described as an example of a scroll type fluid machine. However, the present invention is not limited to this, and may be applied to a vacuum pump, a refrigerant compressor, and the like. Can be applied.

[0067]

As described in detail above, according to the first aspect of the present invention, the boss portion of the orbiting scroll is provided with the orbiting bearing for supporting the orbiting scroll so as to be able to orbit with respect to the crank of the drive shaft, and Since the shaft crank is provided with a grease reservoir for lubricating the slewing bearing, during compression operation, the viscosity of the grease filled in the grease reservoir decreases as the temperature of the slewing bearing rises, so that the grease is swung. The slewing bearing can always be kept in a lubricated state.

As a result, even when the slewing bearing is formed of, for example, a needle bearing or a cylindrical roller having a relatively small internal space volume, the durability and life of the slewing bearing can be improved, and the reliability of the device can be improved. . Further, as described in the related art, it is not necessary to fill the slewing bearing with a larger amount of grease than necessary, and it is possible to prevent the performance of the slewing bearing from being degraded due to the stirring resistance of the grease, and to improve the performance of the slewing bearing. .

According to the second aspect of the present invention, the drive shaft is provided with an opening for opening the grease reservoir into the boss portion, and the opening has a cross-sectional shape smaller than that of the grease accommodating portion. The grease filled in the grease reservoir can be supplied little by little to the slewing bearing side through the opening, so that the grease supply time to the grease reservoir can be extended.

In the third aspect of the present invention, since the opening is disposed at a position eccentric with respect to the rotation center of the drive shaft, the grease in the grease reservoir is moved toward the slewing bearing by the centrifugal force of the drive shaft. The lubrication of the slewing bearing can be further improved by smoothly supplying the slewing bearing.

Further, according to the fourth aspect of the present invention, since the air from the outside is guided to the grease reservoir through the air introducing passage, the grease in the grease reservoir can be supplied more smoothly to the slewing bearing. Can be further enhanced in lubricity.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a scroll type air compressor according to a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part showing a slewing bearing, a grease reservoir and the like in FIG.

FIG. 3 is a partial cross-sectional view showing a grease reservoir, an air introduction path, and the like of a scroll-type air compressor according to a second embodiment of the present invention.

FIG. 4 is an enlarged sectional view of a main part showing a grease reservoir and small holes of a scroll type air compressor according to a third embodiment of the present invention.

FIG. 5 is an enlarged sectional view of a main part showing a grease reservoir, small holes and the like of a scroll type air compressor according to a fourth embodiment of the present invention.

6 shows a crankpin and a cover plate, and is indicated by an arrow VI- in FIG.
FIG. 6 is an enlarged front view as viewed from a VI direction.

FIG. 7 is an enlarged sectional view of a main part showing a grease reservoir, small holes and the like of a scroll type air compressor according to a fifth embodiment of the present invention.

FIG. 8 is a longitudinal sectional view showing a scroll type air compressor according to a sixth embodiment of the present invention.

[Explanation of symbols]

 1,61 Casing 2,62 Fixed scroll 2A, 6A, 62A, 66A End plate 2B, 6B, 62B, 66B Lapping part 3,21,63 Drive shaft 3A, 21A Crank pin 5,65 Orbiting scroll 7,67 Compression chamber 10A, 68A Boss portion 11,69 Slewing bearing 12,22,52,72 Grease reservoir 24,73 Air introduction passage 32,42,54 Small hole (opening) 70 Variable crank 70B Eccentric shaft (crank pin)

Claims (4)

[Claims] 1. A casing, a fixed scroll provided in the casing and having a spiral wrap portion standing upright on a head plate, and a base end side rotatably provided on the casing,
A drive shaft having a crank at the tip end, and a spiral wrap portion which overlaps with the wrap portion of the fixed scroll and defines a plurality of compression chambers are erected on the surface side of the end plate, and a boss portion is provided on the back side of the end plate. A scroll type fluid machine, comprising: a revolving scroll provided with a revolving scroll; and a revolving bearing provided on a boss portion of the revolving scroll and rotatably supporting the revolving scroll with respect to a crank of the drive shaft. A scroll-type fluid machine, wherein a grease reservoir for lubricating the slewing bearing is provided on a shaft crank. 2. The drive shaft is provided with an opening for opening the grease reservoir in a boss portion, and the opening is formed so that a cross-sectional shape in a radial direction of the drive shaft is smaller than a grease accommodating portion. The scroll-type fluid machine according to claim 1. 3. The scroll-type fluid machine according to claim 2, wherein the opening is disposed at a position eccentric with respect to a rotation center of the drive shaft. 4. The drive shaft is provided with an air introduction passage for guiding external air into the grease reservoir, and the air introduction passage is arranged along a rotation center of the drive shaft. 4. The scroll-type fluid machine according to claim 2, 2 or 3.