JP2000227077A - Scroll type compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll type compressor which can reduce the number of components simplify assembling, and improve durable life. SOLUTION: A thrust ball bearing device for preventing autorotation of a movable scroll 20 is provided with a plurality of balls 26 interposed between the first bearing face 20c of the first end plate 20a of the movable scroll 20 and the second bearing face 103c formed on a housing 10, and the first and second bearing faces 20c, 103c have a plurality of ball transfer grooves 20d, 103d transferring balls by the fixed curvature ratio positioning the balls and fixed wrap angle wrapping the balls 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll type compressor, and more particularly to a scroll type compressor having a thrust ball bearing device for preventing the movable scroll from rotating.

[0002]

2. Description of the Related Art In a scroll compressor, a pair of spiral bodies are engaged with each other at an angle, and a relative circular motion (only revolving motion) is given to move a closed space formed between the two spiral bodies toward the center. This is a positive displacement fluid compression device in which the volume is reduced while the compressed fluid is discharged from the center.

As shown in FIG. 5, the scroll compressor of the prior art has a housing 10 forming an outer shell. The housing 10 has a rear housing 101 formed of a large-diameter cylindrical body with a bottom, and a front housing 100. The front housing 100 has a large-diameter cylindrical portion 103 and a small-diameter cylindrical portion 105 fixed to the open end of the rear housing 101. Rear housing 101
And the front housing 100 are arranged with the same central axis.

[0004] A shaft 11 is arranged on a center axis X of the housing 10. The shaft 11 passes through the small-diameter cylindrical portion 105 of the front housing 100 and
Stretching inside. The shaft 11 includes a small-diameter cylindrical portion 11a surrounded by a small-diameter cylindrical portion 105 of the front housing 100 and a large-diameter cylindrical portion 10a of the front housing 100.
3 has a large diameter portion 11b. A drive pin 12 extending parallel to the axis X is eccentrically fixed to the end of the large-diameter cylindrical portion 11b. The large diameter portion 11b of the shaft 11 is rotatably supported by the large diameter portion 11b of the front housing 100 via the needle bearing 13, and the small diameter cylindrical portion 11a is
4, the small-diameter cylindrical portion 10 of the front housing 100
5 rotatably supported.

[0005] An electromagnetic clutch 15 is disposed radially outward of the small-diameter cylindrical portion 105. The electromagnetic clutch 15 is rotatably fitted to the small-diameter cylindrical portion 105, and is connected to an external drive source via a V-shaped belt (not shown).
5a and rotation transmission plate 15 fixed to the end of small diameter portion 11a
c. The drive source drives the shaft 11 to rotate.

In the rear housing 101, a fixed scroll 16 is provided. The fixed scroll 16 includes a disc-shaped end plate 16a that is disposed concentrically with the axis X and fits into the rear housing 101, and a spiral body 16b formed on one surface of the end plate 16a. . A leg 16c is formed on the other surface of the end plate 16a. The rear housing 101 includes a leg 101c projecting from the bottom 101a toward the leg 16c of the end plate 16a. The fixed scroll 16 is fixed to the rear housing 101 by bolts 17 in a state where the distal end surface of the leg 101c is in contact with the distal end surface of the leg 16c of the end plate 16a. The internal space of the rear housing 101 is partitioned into a suction chamber 18 and a discharge chamber 19 by an end plate 16 a of the fixed scroll 16.

A movable scroll 20 is provided in the rear housing 101 adjacent to the fixed scroll 16. The orbiting scroll 20 includes a disc-shaped end plate 20a, a spiral body 20b formed on one surface of the end plate 20a,
And an annular boss 20c formed on the other surface of the end plate 20a. The center axis Y of the end plate 20a is eccentric from the axis X by a distance rs. The scroll 20b of the movable scroll 20 is connected to the scroll 16b of the fixed scroll 16 by one.
They are engaged with a phase difference of 80 degrees.

A thick disk-shaped bush 21 disposed concentrically with the end plate 20a is rotatably fitted in the boss 20c via a needle bearing 22. The bush 21 has an eccentric through-hole 21a extending parallel to the axis X. A balance weight 23 extending in the radial direction is fixed. The through-hole 21a slidably accommodates the drive pin 12 fixed to the large-diameter portion 11b of the shaft 11. A pin (not shown) formed on the bush 21 is fitted in a hole slightly larger in diameter than a pin (not shown) formed on the end of the large diameter portion 11b of the shaft 11.

Further, a doughnut-shaped front housing-side race (lace member) 24 fixed to an end of the large-diameter cylindrical portion 103 of the front housing 100, and a movable scroll 20 shown in an enlarged scale in FIGS. End plate 20a
And a plurality of balls 26 interposed between the front housing-side race 24 and the movable scroll-side race 25 at intervals in the circumferential direction. A thrust ball bearing device (ball coupling) for preventing the movable scroll from rotating is configured. The front housing side race 24 and the orbiting scroll side race 25 face each other via a plurality of balls 26.

The front housing side race 24 has a pair of circular holes (not shown) formed at the outer flange portion thereof, and is formed at the end of the large-diameter cylindrical portion 103 of the front housing 101. Are fixed by a pair of spring pins (not shown) which fit tightly into a pair of holes (not shown).

As shown in FIG. 8, the movable scroll side race 25 has a pair of circular holes 251 formed in the outer peripheral flange portion 25a thereof and the end plate 20 of the movable scroll 20.
a is fixed by a pair of spring pins (not shown) which fit tightly into a pair of holes 203a formed in the hole 203a.
The ball 26 has a plurality of ball transfer grooves 24c formed in the front housing side race 24 and the ball transfer groove 2c.
4c, it is interposed between the front housing side race 24 and the movable scroll side race 25 while being sandwiched by the ball transfer groove 25c formed in the movable scroll side race 25 so as to face the 4c.

A plurality of balls 2 interposed between the front housing side race 24 and the movable scroll side race 25
6, the thrust ball bearing device for preventing the movable scroll from rotating has its own turning radius.

In the conventional scroll compressor, the fixed scroll 16, the movable scroll 20, and the front housing 100 are usually made of an aluminum-based material to reduce the weight. The fixed scroll 16, the movable scroll 20, and a pair of race members 24 made of an iron-based material are provided on the front housing 100.
The structure is such that a ball 26 is interposed between the balls 25.

[0014] Therefore, due to the problem of durability, the portion that is directly subjected to the surface pressure from the ball 26 is a race member made of a harder iron-based component. The race members 24 and 25 are fixed not only by pins but also by caulking. Also,
The shape of the ball transfer grooves 24c and 25c is formed by press molding.

[0015]

In the case of a thrust ball bearing device for preventing rotation of a movable scroll, the ball itself is turned by a plurality of balls 26 interposed between a race 24 on a front housing side and a race 25 on a movable scroll side. Has a radius.

On the other hand, at the time of actual operation, the movable scroll 20 tends to move at the turning radius of the movable scroll 20 itself. However, at the time of actual production, there is a problem that a difference occurs between the two turning radii due to a processing error or the like, the performance is reduced, and the life of the thrust ball bearing device for preventing the movable scroll 20 from rotating is reduced. is there.

Since the shape of the ball transfer grooves 24c and 25c is formed by press molding, it is convenient for accuracy. 1st place is the limit)
Therefore, the groove curvature ratio of the ball transfer grooves 24c and 25c (the radius of the ball transfer groove / the radius of the ball) is limited to about 1.1. Therefore, although the bearing life is improved as compared with a flat surface, the bearing life is close to a point contact.

The lace members 24 and 25 formed by press forming have a small wrapping angle, which is inconvenient in terms of durability and assembly. If the wrap angle is increased, the accuracy of the ball transfer grooves 24c and 25c described above deteriorates, and there is a problem that the curvature ratio of the ball transfer grooves 24c and 25c has to be set in a direction in which the durability deteriorates.

Conventionally, the position accuracy is determined by the race members 24, 25.
Is determined by the press accuracy of the ball transfer grooves 24c and 25c to the holes and the accuracy of the fixed pin holes.
There is a problem that the positional accuracy of 4c and 25c is not constant.

If the position of the ball transfer groove 24c of the orbiting scroll 20 deviates from the ideal position, the ball 26 and the ball transfer groove 24c do not come into contact with each other at the ideal contact position. There is a problem that arises.

Further, at the time of assembly, the ball 26 may fall from the ball transfer grooves 24c and 25c in a semi-finished state.

Therefore, an object of the present invention is to provide a scroll compressor in which the number of parts can be reduced and assembly can be simplified.

Another object of the present invention is to provide a scroll type compressor which is capable of improving the hardness of the ball transfer groove and performing good oil lubrication on the ball transfer groove, and having excellent durability. It is in.

[0024]

According to the present invention, a housing, a fixed scroll provided in the housing, a movable scroll provided in the housing in close proximity to the fixed scroll, and rotation of the movable scroll are provided. A movable thrust ball bearing device for preventing the movement of the movable scroll, wherein the movable scroll has a first end plate and a first end plate provided on one surface of the first end plate.
Wherein the fixed scroll has a second end plate fixed to the housing facing the first end plate in the housing and a second scroll provided on one surface of the second end plate. A closed space formed between the first and second scrolls by engaging the first and second scrolls at different angles and revolving the movable scroll. In a scroll type compressor that discharges a compressed fluid while reducing the volume while moving in the center direction, the thrust ball bearing device includes a first bearing surface opposite to a surface of the first end plate; A second bearing surface of the housing facing the first bearing surface, and a plurality of balls interposed between the first and second bearing surfaces, wherein the first and second bearing surfaces are the balls A predetermined groove curvature ratio and a predetermined wrap around the ball It scroll compressor can be obtained, characterized in that a plurality of balls transfer groove to transfer with a.

[0025]

According to the scroll type compressor of the present invention, the ball is provided on the first bearing surface of the spiral body (first spiral body) of the movable scroll and the second bearing surface of the front housing by using a jig such as a ball end mill. Process the transfer groove. By this machining, the wrap angle that wraps the ball is approached to an angle of 180 degrees. Since the accuracy of the ball transfer groove is also improved as compared with the conventional press molding, it is possible to design the groove curvature ratio (groove radius / ball radius) of the ball transfer groove to be close to 1.

In machining, a tolerance of ± 2 decimal places is possible for the tolerance of several millimeters of the radius of the ball transfer groove at the machining level when machining the conventional movable scroll and front housing.

Further, if necessary, the surface of the ball transfer groove is subjected to a surface treatment such as alumite to increase the hardness of the surface of the ball transfer groove. When the front housing and the movable scroll are made of an aluminum-based material, alumite having a higher hardness than the aluminum-based material is subjected to a surface treatment.

Further, as the wrap angle approaches the angle of 180 degrees, the oil lubrication of the ball deteriorates. Therefore, an additional groove for oil lubrication is added in a direction tangential to the ball transfer groove and in a direction to take in suction gas during rotation. . Therefore, these configurations are satisfied even if the material of the ball transfer groove is an aluminum-based material.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a scroll compressor according to the present invention will be described below with reference to the accompanying drawings. Since the scroll type compressor has substantially the same configuration as the scroll type compressor having the configuration described in FIG. 5, the same portions are denoted by the same reference numerals, and the configuration of the portion provided with the thrust ball bearing device of the present invention and Parts related to this configuration will be described, and description of other parts having the same configuration will be omitted.

The movable scroll 20 is provided with a spiral body (first spiral body) 20b on one surface of an end plate (first end plate) 20a. The end plate 20a of the movable scroll 20
Has a first bearing surface 20c on a surface opposite to one surface. The front housing 100 has a second bearing surface 103c on the end surface of the large-diameter cylindrical portion 103. The first bearing surface 20c of the orbiting scroll 20 faces the second bearing surface 103c of the large-diameter cylindrical portion 103.

A plurality of balls 26 are interposed between the first and second bearing surfaces 20c, 103c. As shown in FIG. 2, the first bearing surface 20c has a plurality of first ball transfer grooves 20d for transferring the ball 26 with a predetermined groove curvature ratio and a predetermined wrapping angle surrounding the ball 26. . The second bearing surface 103c has a plurality of second ball transfer grooves 103d for transferring the ball 26 with a predetermined groove curvature ratio and a predetermined wrap angle surrounding the ball 26.

Here, the first and second bearing surfaces 20c, 1
03c, ball 26 and first and second ball transfer grooves 2
Reference numerals 0d and 103d form a thrust ball bearing device for preventing the movable scroll 20 from rotating.

The movable scroll 20 and the front housing 100 are made of the same material, a first ball transfer groove 20d is formed in the first bearing surface 20c, and a second ball transfer groove 103d is formed in the second ball transfer groove 103d. Is formed by machining on the bearing surface 103c.

Specifically, the movable scroll 20 and the front housing 100 employ an aluminum-based material. For example, in the front housing 100 using the same aluminum-based material as the movable scroll 20 using the aluminum-based material, the first and second ball transfer grooves 20d, which have an ideal groove curvature ratio and a wrap angle that wraps the ball 26, are provided. 103d is obtained by machining.

The first and second ball transfer grooves 20d and 103d are formed on the first and second bearing surfaces 20c and 103c by using a jig such as a ball end mill. When the wrapping angle is approached to the angle of 180 degrees by this machining, the precision of the first and second ball transfer grooves 20d and 103d is improved as compared with the conventional press molding. That is, it is possible to design the groove curvature ratio of the first and second ball transfer grooves 20d and 103d (radius of ball transfer groove / radius of ball) to be close to 1.

In the machining, the current spiral body 20 is used.
b, the tolerance of the groove radius of several mm at the processing level of the front housing 100 can be as high as the second place after the decimal point. Specifically, when the diameter of the ball 26 is 8 mm, the first and second ball transfer grooves 2 formed by machining are used.
0d and 103d, the positional accuracy of the first and second ball transfer grooves 20d and 103d is ± 0.05,
And radius accuracy of the second ball transfer grooves 20d and 103d
0.05, first and second ball transfer grooves 20d, 103
d radius R 4.1, first and second ball transfer grooves 20
The groove curvature ratio of d and 103d is 1.025.

The first and second ball transfer grooves 20
The radius of each of the first and second ball transfer grooves 2
When the positions and radii of 0d and 103d have the worst dimensional tolerance, the first
The radius of the ball 26 is set to be smaller than or equal to the radius of the second ball transfer grooves 20d and 103d.

Incidentally, the ball transfer grooves 24 are formed in the race members 24 and 25 by the conventional press working shown in FIGS.
c, 25c, the ball transfer grooves 24c,
Position accuracy of 25c ± 0.2, ball transfer groove 24c, 2
5c is a radius accuracy of 0.2, the radius R4.4 of the ball transfer grooves 24c, 25c is R4.4, and the groove curvature ratio 1.1 of the ball transfer grooves 24c, 25c is the first decimal place tolerance.

In the scroll compressor having the above-described thrust ball bearing device, the ball 26 revolves in the first and second ball transfer grooves 20d and 103d as the movable scroll 20 revolves. The vehicle rolls along a circular orbit having substantially the same radius as the radius rs. Further, as the orbit of the movable scroll 20 revolves, the balls 26 are pressed against the first and second ball transfer grooves 20d and 103d, and the first and second ball transfer grooves 20d and 10d.
It is possible to smoothly roll in 3d by drawing a circular orbit with a radius substantially equal to the orbital radius rs of the movable scroll 20. As a result, the movable scroll 20 is moved to the front housing 10.
0, and thus revolves while maintaining a predetermined angular relationship with respect to the fixed scroll 16.

If necessary, the surface of the first and second ball transfer grooves 20d and 103d is subjected to a surface treatment,
The hardness of the surface of the first and second ball transfer grooves 20d and 103d is increased. That is, the first and second ball transfer grooves 20
The surfaces of d and 103d are subjected to a surface treatment with a surface treatment member such as alumite having a higher hardness than the material of the movable scroll 20 and the front housing 100.

Here, when the front housing 100 and the movable scroll 20 are made of an aluminum-based material, alumite having a higher hardness than the aluminum-based material is subjected to surface treatment.

FIG. 3 shows a second embodiment of the scroll type compressor according to the present invention.
1 shows an embodiment of the present invention. Since the scroll compressor has the same configuration as the scroll compressor having the configuration described with reference to FIGS. 1 and 2, the same portions are denoted by the same reference numerals and the description of the same portions will be omitted.

The first and second ball transfer grooves 20d, 10d
In 3d, as the wrap angle approaches an angle of 180 degrees, oil lubrication to the ball 26 may be deteriorated.
Therefore, on the first bearing surface 20c, there is a single first ball transfer groove 2 between the plurality of first ball transfer grooves 20d.
A first additional groove 20g for lubricating oil extends from a part of Od to a peripheral end of the first bearing surface 20c. Further, the first additional groove 2 is also provided on the second bearing surface 103c.
A second additional groove (not shown) is formed as in the case of Og. Therefore, in the following description, the first additional groove 20g
And only the description of the second additional groove will be omitted.

The first additional groove 20g is added in a direction tangential to the first ball transfer groove 20d and in a direction to take in the suction gas during rotation. The shape of the first ball transfer groove 20d is a curved groove such as an involute or a spiral on the first bearing surface 20c. Each first ball transfer groove 2
0d, the movable scroll 20 rotates at the rotation angle in the direction of the arrow shown in FIG. 3, and at this time, oil flows from the peripheral end of the first additional groove 20g into the first ball transfer groove 20d, and the ball 26 Lubrication is performed on the contact surface with the first ball transfer groove 20d surface.

Therefore, these first additional grooves 20
g, and the configuration of the second additional groove, this is true even if the material of the first and second ball transfer grooves 20d and 103d is aluminum.

[0046]

As described above, according to the scroll type compressor of the present invention, the conventional race member is not required and the mechanism for fixing the race member is eliminated, so that the number of parts can be reduced and the assembly is simplified. Therefore, it is possible to provide a scroll compressor having excellent economy.

In addition, the positional accuracy of the ball transfer grooves is reduced only by the processing accuracy of the groove position, and the surface pressure variation of each ball is reduced, so that the life is improved. If this is designed to improve the groove curvature ratio and the wrapping angle, add surface treatment such as alumite, and select additional grooves for oil lubrication, the conventional race member can be used even though the contact surface is made of aluminum. On the other hand, it has the effect of having the same or more durable life.

[Brief description of the drawings]

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

FIG. 2 is a side view of the movable scroll shown in FIG. 1 as viewed from the left side.

FIG. 3 is a plan view showing a second embodiment of the scroll compressor according to the present invention, in which the movable scroll is viewed from the left side.

FIG. 4 is a sectional view taken along line III-III of FIG. 3;

FIG. 5 is a cross-sectional view showing a conventional scroll compressor.

FIG. 6 is a sectional view of the orbiting scroll shown in FIG. 5;

7 is a plan view of the movable scroll shown in FIG. 5 as viewed from the left side.

FIG. 8 is a plan view showing a movable scroll-side race member shown in FIG. 5;

[Explanation of symbols]

 Reference Signs List 10 housing 11 shaft 11a small-diameter cylindrical portion 11b large-diameter cylindrical portion 16 fixed scroll 16a end plate 18 suction chamber 19 discharge chamber 20 movable scroll 20a end plate 20c first bearing surface 20d first ball transfer groove 20g additional groove 24 movable scroll Side race (lace member) 25 Fixed scroll side race (race member) 24c, 25c Ball transfer groove 26 Ball 100 Front housing 101 Rear housing 103c Second bearing surface 103d Second ball transfer groove 105 Small diameter cylindrical portion

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 3H029 AA02 AA15 AA21 BB31 BB32 BB44 CC05 CC08 CC17 CC38 3H039 AA02 AA12 BB05 BB07 BB08 CC02 CC09 CC18 CC23 CC35 CC36 3J101 AA02 AA53 AA62 AA71 BA70 BA14 FA14 FA29

Claims (7)

[Claims] 1. A housing, a fixed scroll provided in the housing, a movable scroll provided in the housing in close proximity to the fixed scroll, and a thrust ball bearing device for preventing the movable scroll from rotating. Wherein the movable scroll has a first end plate and a first spiral body provided on one surface of the first end plate, and the fixed scroll is attached to the first end plate in the housing. A second end plate fixed to the housing facing the second end plate, and a second spiral body provided on one surface of the second end plate, wherein the first and second spiral bodies are shifted in angle. In a scroll compressor, the orbiting scroll is provided with a revolving motion so as to move a closed space formed between the first and second spiral bodies toward a center direction while reducing a volume and discharging a compressed fluid. Suras The ball bearing device includes a first bearing surface opposite to one surface of the first end plate, a second bearing surface of the housing facing the first bearing surface, and a first and a second bearing surface. A plurality of balls having a plurality of balls interposed between the bearing surfaces, wherein the first and second bearing surfaces are transferred at a predetermined groove curvature ratio for positioning the balls and at a predetermined wrap angle surrounding the balls; A scroll compressor having a groove. 2. The scroll type compressor according to claim 1, wherein said movable scroll and said housing are made of the same material, and wherein said ball transfer groove is formed by machining. . 3. The scroll-type compressor according to claim 2, wherein said movable scroll and said housing are made of an aluminum-based material. 4. The scroll type compressor according to claim 1, wherein the surface of the ball transfer groove is subjected to a surface treatment by a surface treatment member having a hardness higher than that of a material of the movable scroll and the housing. A scroll type compressor characterized by being made. 5. The scroll compressor according to claim 4, wherein said surface treatment member is alumite. 6. The scroll type compressor according to claim 1, wherein said first and second bearing surfaces are formed at respective peripheral ends of said first and second bearing surfaces from said respective ball transfer grooves. A scroll compressor having an additional oil lubrication groove extending therefrom. 7. The scroll type compressor according to claim 6, wherein said additional groove is added in a direction tangential to said ball transfer groove and in a direction to take in suction gas during rotation. .