JP2003286975A - Scroll compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a swing bearing 1a from being damaged by the edge of an oil groove 3b when a load in reverse direction acts on the swing bearing 1a of a scroll compressor. <P>SOLUTION: This scroll compressor comprises a spindle 2 for driving a swing scroll 1 by a drive bush 3 through the swing bearing 1a. The oil groove 3b is formed in the outer peripheral surface of the swing bush 3 parallel with the axial direction of the spindle 2 at a position on the opposite side of a compression load acting side, in the direction opposite to the relative rotational direction of the swing bearing 1a, and in the angular area of 0 to 60° relative to a straight line obtained by connecting the center of the drive bush to the rotational center of the spindle 2. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scroll compressor used for an air conditioner, a refrigerator, and the like, and more particularly to improvement of a drive mechanism having a drive bush for transmitting the rotation of a main shaft to an orbiting scroll.

[0002]

2. Description of the Related Art A conventional scroll compressor in which a drive bush is fitted to an eccentric pin of a main shaft and an orbiting scroll is rotated through the drive bush, and FIG. 4 is a cross-sectional view of an essential part for explaining an oil groove of the drive bush. FIG. 5 is a perspective view of relevant parts for explaining a state where the drive bush is fitted to the eccentric pin of the main shaft. In these drawings, 2 is a main shaft, 2a is an eccentric pin that eccentrically projects from the end of the main shaft 2 with respect to the shaft center, 3 is a drive bush, 3a is a hole provided in the drive bush 3, 3b is an outer periphery of the drive bush 3, It is an oil groove provided parallel to the axial direction of the main shaft 2.

The drive bush 3 has a hole 3a in the eccentric pin 2a.
Are fitted together. At this time, the engaging load surface 2b of the eccentric pin 2a, which is a plane parallel to the axial direction of the main shaft 2, engages so as to face a similar plane formed on the inner surface of the drive bush hole 3a. 2e is a rotation center of the main shaft 2, 3e is a center of the drive bush 3, a straight line L1 is a straight line connecting a rotation center 2e of the main shaft 2 and a rotation center 3e of the drive bush 3, and a straight line L2 is a center 2e of the drive bush 3. Is a straight line connecting the center of the oil groove 3b and the angle δ formed by L1 and L2 is 90
It is set to ° to 180 °. The white arrow in FIG. 4 indicates the direction of rotation of the main shaft.

Next, the force acting on the rocking bearing 1a when the scroll compressor is operating will be described with reference to FIG. When the scroll compressor is operating, that is, when the oscillating bearing 1a rotates relative to the drive bush 3 in the direction of the white arrow (in FIG. 6, the oscillating bearing-
The relative compression direction between the drive bushes) and the gas compression load from the orbiting scroll act on the orbiting bearing 1a in the direction of the white arrow.

On the other hand, when the compressor is not in operation and the supply of electric power to the electric motor is stopped and the torque for driving the main shaft 2 is lost, the compressed gas in the compression chamber expands and the main shaft 2 is operated when the compressor is in operation. And rotate it in the opposite direction. Since the main shaft 2 and the orbiting scroll rotate in the opposite direction due to inertia even after the gas inside the compression chamber expands to the same pressure as the pressure outside the compression chamber,
Since the pressure inside the compression chamber is lower than that outside the compression chamber, as shown in FIG. 7, the load in the opposite direction to that during normal operation of the compressor,
That is, the reverse load acts on the drive bush 3.

FIG. 8 schematically shows the condition of lubricating oil between the rocking bearing 1a and the drive bush 3 during operation of the compressor. The oscillating bearing 1a forms a so-called sliding bearing with respect to the drive bush 3, and the lubricating oil supplied to the bearing surface from the oil groove 3b of the drive bush 3 rotates relative to the drive bush 3 of the oscillating bearing 1a. As a result, they are carried in the direction indicated by the white arrow, that is, in the relative sliding direction of the rocking bearing 1a and the drive bush 3, and flow toward the engagement load surface 2b side.

At this time, the rocking bearing 1a and the drive bush 3
The oil film formed between them causes an oil film pressure to support the gas compression load (indicated by a white arrow) of the orbiting scroll.
The minimum oil film formation position X in the oscillating bearing 1a is eccentric with respect to the gas compression load direction, and normally the eccentric angle of 20 to 50 degrees (in the drawing by θ in the figure is in the relative movement direction of the oscillating bearing 1a. Shown). This eccentric angle changes within this range depending on the load on the compressor, the viscosity of the lubricating oil, and the like. In the plain bearing, the fluid oil film pressure is generated in a section 180 ° from the minimum oil film formation position X (shown as a fluid oil film pressure generation section Y in the figure), and the fluid oil film pressure opposite to the bearing load is not generated in other sections. .

[0008]

The drive mechanism having the drive bush of the conventional scroll compressor is constructed as described above, and the oil groove of the drive bush 3b rotates the main shaft 2 as shown in FIG. In the scroll compressor in which δ is set to around 90 ° in the rotation direction of the main shaft 2 from the straight line L1 connecting the center 2e and the center of the drive bush 3e, the reverse load when the scroll compressor is stopped is not affected by the oil groove 3b. There is a problem that the rocking bearing 1a is damaged by the edge of the oil groove 3b.

Further, as shown in FIG. 6 (also FIG. 8),
When the set angle δ of the oil groove 3b is large, the oscillating bearing 1 by the edge of the oil groove 3b is caused by the reverse load at the time of stop.
Although damage to a can be prevented, during normal operation, the distance from the oil groove 3b to the fluid oil film pressure generation section (Y) becomes large, and the length of the lubricating oil that leaks in the axial direction becomes long during the operation. However, there is a problem that the amount of lubricating oil supplied to the oil film pressure generation section (Y) is reduced, causing abnormal wear and seizure of the rocking bearing 1a.

FIG. 9 is a longitudinal sectional view of an essential part showing a state in which the drive bush and the oscillating bearing of the conventional scroll compressor are in one-side contact with each other. A load in the reverse direction is applied to the drive bush 3 when the compressor is stopped. The case where it worked (FIG. 7 above) is shown. Since there is a gap between the eccentric pin 2a and the rocking bearing 1a other than the intervening drive bush 3, a gap exists between the drive bush 3 and the rocking bearing 1a.
There is a problem that "a" cannot be maintained in parallel and is tilted to a one-sided contact state, the surface pressure locally rises, and abnormal wear occurs in the rocking bearing 1a.

The present invention has been made to solve the above problems, and provides a scroll compressor in which the rocking bearing is not damaged by the oil groove edge even when a reverse load is applied when the compressor is stopped. The purpose is to Another object of the present invention is to obtain a scroll compressor in which a sufficient oil film can be formed between the drive bush and the rocking bearing during normal operation, and the load capacity of the rocking bearing increases. Further, even if the eccentric pin tilts with respect to the drive bush due to a gas compression load, the drive bush can maintain parallel engagement with the oscillating bearing, preventing abnormal wear and seizure of the oscillating bearing. Aim to get. Further, even if the eccentric pin tilts with respect to the drive bush due to a reverse load, the drive bush can maintain parallel engagement with the oscillating bearing and prevent abnormal wear and seizure of the oscillating bearing. Aim to get.

[0012]

A scroll compressor according to claim 1 of the present invention comprises a fixed scroll and an orbiting scroll which form a compression chamber when combined with each other, and an eccentric pin which is rotated by an electric motor. A scroll compressor having a drive shaft engaged with the eccentric pin and driving an oscillating scroll through an oscillating bearing, the outer peripheral surface of the drive bush being parallel to the axial direction of the drive shaft. The oil groove is formed, and the position of the oil groove is oscillated on the side opposite to the side on which the compression load acts on the scroll compressor with respect to the straight line connecting the center of the drive bush and the center of rotation of the main shaft. The bearing is formed in an angle range of 0 to 60 degrees from the straight line in the direction opposite to the relative rotation direction of the bearing, and oil is supplied between the drive bush and the rocking bearing by an oil groove to which lubricating oil is supplied.

The scroll compressor according to a second aspect is the scroll compressor according to the first aspect, wherein at least one of the engaging portions of the drive bush and the eccentric pin is engaged during operation of the scroll compressor. A convex portion is formed along the axial direction of the main shaft on the side on which the compressive load acts.

The scroll compressor according to claim 3 is the scroll compressor according to claim 1 or 2, wherein:
At least one of the engaging portions of the drive bush and the eccentric pin forms a convex portion along the axial direction of the main shaft on the side where the reverse rotation occurs when the scroll compressor stops operating and the reverse load acts. To do.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. FIG. 1 is a vertical sectional view showing the scroll compressor according to the first embodiment. Also,
FIG. 2 is a sectional view of relevant parts for explaining the oil groove of the drive bush. In these figures, 1 is an orbiting scroll,
Reference numeral 1a is a rocking bearing, 2 is a main shaft, 2a is an eccentric pin that eccentrically projects from the end of the main shaft 2 with an axial center, 2b is an engagement load surface of the eccentric pin 2a, and 2f is a second engagement load surface. Reference numeral 3 denotes a drive bush that is rotatably fitted to the rocking bearing 1a, and 3b denotes an oil groove formed on the outer peripheral surface of the drive bush 3 in the axial direction of the drive bush 3 (axially of the main shaft 2). A fixed scroll, 8 is an electric motor, 9 is an oil pump, and 10 is an oil sump.

In FIG. 2, the rotation direction of the main shaft 2 is the same as in FIG. 4, and the relative movement direction between the rocking bearing 1a and the drive bush 3 is the same as in FIGS.
That is, the rocking bearing 1a rotates relative to the drive bush 3 as indicated by the white arrow. Also, the action direction of the gas compression load during normal operation of the compressor and the action direction of the reverse load during rotation of the compressor in the opposite direction when the compressor is stopped are shown in FIG. 6 (FIG. 8) and FIG. Is the same as. Also, the straight line L
Reference numeral 1 is a straight line connecting the rotation center 2e of the main shaft 2 and the rotation center 3e of the drive bush 3 in the centrifugal direction when the orbiting scroll 1 is rotated. The engagement load surface 2b of the eccentric pin 2a is a plane parallel to the straight line L1 direction, that is, the centrifugal direction and the axial direction of the main shaft 2, and the compression load is normal to the straight line L1 during normal operation of the compressor. On the acting side, it is a plane orthogonal to the direction in which this compressive load acts, and is engaged with a similar plane formed on the inner surface of the hole 3a of the drive bush 3.

In the present embodiment, as shown in FIG. 2, the oil groove 3b formed in the drive bush 3 is provided on the side facing the engagement load surface 2b, that is, the center 3e of the drive bush 3 and the main shaft 2. The compressor is provided on the side opposite to the side on which the gas compression load is applied during normal operation with respect to the straight line L1 connecting the rotation center 2e, and the straight line L1, the center of the oil groove 3b and the center 3e of the drive bush 3 are arranged. The angle formed by the connecting straight line L2 and the straight line L1
From 0 to 6 in the direction opposite to the relative rotation direction of the rocking bearing 1a.
Set to 0 degrees.

The compression operation of the scroll compressor will be described.
The main shaft 2 is rotated by an electric motor 8 and drives the orbiting scroll 1 via an eccentric pin 2a and a drive bush 3. The orbiting scroll 1 forms a compression chamber in cooperation with the fixed scroll 4 and compresses the refrigerant gas in the compression chamber. Also, the oil sump 10
The oil is guided by the oil pump 9 to the oil groove 3b through an oil passage (not shown) formed in the main shaft 2 in the axial direction.

Next, the oil groove 3b formed in the drive bush 3
The refueling action of will be described. An oil film is formed between the drive bush 3 and the rocking bearing 1a by the normal operation of the compressor,
The point that the oil film pressure is generated in response to the gas compression load is the same as that described in the related art. In this embodiment,
Since the formation position of the oil groove 3b is as described above, even if the reverse load is applied when the scroll compressor is stopped, the acting direction of the reverse load and the formation position of the oil groove 3b are deviated from each other. It is possible to prevent the rocking bearing 1a from being damaged by the edge of. Further, the formation position of the oil groove 3b is close to the fluid oil film pressure generation section Y, and particularly close to the minimum oil film formation position X,
Oil can be supplied up to the minimum oil film formation position X, sufficient oil film pressure can be formed, and the load capacity of the rocking bearing 1a increases.

On the other hand, when the formation position of the oil groove 3b is formed in the vicinity of the engagement load surface 2b side with respect to the straight line L1 in FIG. 2, for example, the oil film formation region is reduced, that is, up to the minimum oil film formation position X. And the load capacity of the bearing is reduced. Further, when it is formed in the vicinity of B, oil is leaked from the bearing end portion in the axial direction while the lubricating oil is transferred to the fluid oil film pressure generation section Y, and the oil supply becomes insufficient. The engagement load surface 2b and the engagement load surface 2g may be either ones, and if there is a means for driving the drive bush 3 by the eccentric pin 2a, the engagement load surface 2b and the engagement load surface 2g may be It may not be provided.

Embodiment 2. FIG. 3 is a cross-sectional view of a main part for explaining the shape of the eccentric pin of the scroll compressor according to the second embodiment. In the present embodiment, in the first embodiment, the convex portion 2f in the direction along the axial direction of the main shaft 2 is provided on the second engagement load surface 2g of the eccentric pin 2a opposite to the engagement load surface 2b.
Is formed. Other configurations are the same as those in the first embodiment. The second engagement load surface 2g of the eccentric pin 2a is a plane parallel to the straight line L1 direction, that is, the centrifugal direction and the axial direction of the main shaft 2, and is compressed in the opposite direction to the straight line L1 when the compressor is stopped. It is the plane on which the load acts, and is engaged with a similar plane formed on the inner surface of the hole 3a of the drive bush 3. In the present embodiment, when the operation of the compressor is stopped, the main shaft 2 rotates in the opposite direction, the load in the opposite direction to that in the normal operation acts on the drive bush 3, and the main shaft 2 tilts to drive the eccentric pin 2a. Even if the drive bush 3 is tilted with respect to the bush 3, the driving bush 3 can maintain parallel engagement with the rocking bearing 1a, prevent one-sided contact, and prevent abnormal wear and seizure of the rocking bearing 1a.

In the present embodiment, the convex portion 2f is formed on the second engaging surface 2g, but it is also effective to form the convex portion in the axial direction of the main shaft 2 on the corresponding portion of the drive bush 3. Are the same. Further, the second engaging surface 2g is not provided, and the eccentric pin 2a is
The same effect can be obtained by forming a convex portion in a direction along the axial direction of the main shaft 2 on at least one of the engaging portions of the drive bush 3 on the side where the load in the reverse direction acts.

In the above first embodiment, the second embodiment
Similarly, when a gas compressive load acts by forming a convex portion along the axial direction of the main shaft 2 on at least one of the engaging portions of the eccentric pin 2a and the drive bush 3 on the side where the compressive load acts. Even if the eccentric pin 2a is inclined, the parallel engagement between the drive bush 3 and the rocking bearing 1a can be maintained.
The bearing load of a can be increased. The convex portion provided on at least one of the engaging portion of the eccentric pin 2a and the drive bush 3 may be provided with either one of the convex portion on the gas compression load side and the convex portion on the reverse load side. Well, each effect is played.

[0024]

As described above, the scroll compressor according to claim 1 of the present invention is rotated by an electric motor and a fixed scroll and an orbiting scroll that form a compression chamber when combined, and an eccentric pin is provided at the tip. A scroll compressor having a drive shaft engaged with the eccentric pin and driving an oscillating scroll through an oscillating bearing, the outer peripheral surface of the drive bush being parallel to the axial direction of the drive shaft. An oil groove is formed, and the position of the oil groove is located on the side opposite to the side on which the compression load acts on the scroll compressor with respect to the straight line connecting the center of the drive bush and the rotation center of the main shaft,
Since it is formed in an angle range of 0 to 60 degrees from the straight line in the direction opposite to the relative rotation direction of the rocking bearing, and oil is supplied between the drive bush and the rocking bearing by an oil groove to which lubricating oil is supplied, The rocking bearing is not damaged by the oil groove edge even when a reverse load is applied at the time of stop, and during normal operation, the oil groove formation position is close to the oil film pressure formation area, and oil is supplied to the minimum oil film formation position. It is possible, sufficient oil film pressure can be formed, and the load capacity of the rocking bearing increases.

A scroll compressor according to a second aspect is the scroll compressor according to the first aspect, wherein at least one of the engaging portions of the drive bush and the eccentric pin is
On the side where the compression load acts when the scroll compressor is operating,
Since the convex portion is formed along the axial direction of the main shaft, even if the gas compression load acts and the eccentric pin tilts with respect to the drive bush,
The drive bush can maintain parallel engagement with the rocking bearing, and can prevent abnormal wear and seizure of the rocking bearing.

A scroll compressor according to a third aspect is the scroll compressor according to the first or second aspect, wherein at least one of the engaging portions of the drive bush and the eccentric pin is engaged with the scroll compressor. When the eccentric pin is tilted with respect to the drive bush due to the reverse load, it reversely rotates when the operation is stopped and forms a convex portion along the axial direction of the main shaft on the side where the reverse load acts. The bush can maintain parallel engagement with the rocking bearing, and can prevent abnormal wear and seizure of the rocking bearing.

[Brief description of drawings]

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

FIG. 2 is a horizontal cross-sectional view of an essential part for explaining an oil groove of a drive bush of the scroll compressor according to the first embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of an essential part for explaining the shape of an eccentric pin of a scroll compressor according to a second embodiment of the present invention.

FIG. 4 is a cross-sectional view of a main part for explaining an oil groove of a drive bush of a conventional scroll compressor.

FIG. 5 is a perspective view of relevant parts for explaining a state where a drive bush is fitted to an eccentric pin of a conventional scroll compressor.

FIG. 6 is a cross-sectional view of a main part for explaining a force acting on a rocking bearing of a conventional scroll compressor.

FIG. 7 is a transverse cross-sectional view of an essential part for explaining a force acting on a drive bush due to reverse rotation of a conventional scroll compressor.

FIG. 8 is a transverse cross-sectional view of a main part for explaining a situation of lubricating oil between a rocking bearing and a drive bush during operation of a conventional scroll compressor.

FIG. 9 is a longitudinal sectional view of an essential part for explaining a one-sided contact state between a drive bush and a rocking bearing of a conventional scroll compressor.

[Explanation of symbols]

1 oscillating scroll, 1a oscillating bearing, 2 spindle, 2a
Eccentric pin, 2f convex part, 3 drive bush, 3b oil groove, 4 fixed scroll, 8 electric motor.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yusuke Shimazu             2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo             Inside Ryo Electric Co., Ltd. F term (reference) 3H029 AA02 AA14 AB03 BB44 CC08                 3H039 AA03 AA06 AA12 BB04 BB11                       CC10 CC12 CC13

Claims (3)

[Claims] 1. A fixed scroll and an orbiting scroll which form a compression chamber when combined with each other, an eccentric pin which is rotated by an electric motor, has an eccentric pin at its tip, and an oscillating bearing by a drive bush engaged with the eccentric pin. In a scroll compressor provided with a main shaft for driving the orbiting scroll via, an oil groove is formed on an outer peripheral surface of the drive bush in parallel to an axial direction of the main shaft, and a position of the oil groove is set. , A direction opposite to the relative rotation direction of the rocking bearing on the side opposite to the side on which the compression load is applied when the scroll compressor operates, with respect to the straight line connecting the center of the drive bush and the rotation center of the main shaft. To form an angle range of 0 to 60 degrees from the straight line,
A scroll compressor, wherein oil is supplied between the drive bush and the rocking bearing by the oil groove to which lubricating oil is supplied. 2. A projection along the axial direction of the main shaft on the side on which a gas compression load is applied at the time of operation of the scroll compressor in at least one engagement portion of the engagement portions of the drive bush and the eccentric pin. The scroll compressor according to claim 1, wherein the scroll compressor forms a part. 3. At least one of the engaging portions of the drive bush and the eccentric pin is reversely rotated when the scroll compressor is stopped, and a reverse load acts on the side of the main shaft. The scroll compressor according to claim 1 or 2, wherein a convex portion is formed along the axial direction.