JP2000130364A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slide bush suitable for miniaturizing a device and reducing the number of working man-hours by forming the slide bush into the cylindrical shape having the approximately uniform outer diameters from one end surface to the other end surface, and forming a recessed part covering an opening of an oil feed passage and communicated to an inner peripheral surface of the slide bush on a lower end surface of the slide bush. SOLUTION: An approximately cylindrical slide bush 1 is freely engaged with an eccentric part 2a of a crankshaft 21 communicated to a rotor of a motor. The slide bush 1 has the cylindrical shape having the approximately uniform outer diameter from an upper end surface to a lower end surface, and does not have a flange part. The slide bush 1 comprises a recessed part 1a on its lower end surface, and this recessed part 1a is communicated to an inner peripheral surface of the slide bush 1. The recessed part 1a is formed into the shape of a crescent avoiding a diagonal groove formation area, communicated to the inner peripheral surface and a cutout part of the slide bush 1, and covers an opening end of an oil feed passage 2b formed on a crankshaft 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a scroll type fluid machine, and more particularly, to a scroll type fluid machine having a slide bush.

[0002]

BACKGROUND ART As an example of a scroll-type fluid machine having a slide bush, Japanese Patent Application No. 9-155053 (19)
(Filed on June 12, 1997) has been proposed by the present applicant. Hereinafter, the scroll compressor in this application will be described.

FIG. 7 is a partial sectional view schematically showing the structure of the scroll compressor in the above-mentioned application. Referring to FIG. 7, an eccentric pin portion 102a is provided at an upper end of crankshaft 102 connected to the rotor of the motor. A discharge gas passage 102c for passing the refrigerant gas discharged from the compression element and an oil supply passage 102b for passing the oil are provided in the crankshaft 102 in parallel in the axial direction.

A cylindrical slide bush 101 is loosely fitted into the eccentric pin portion 102a. In this state, the eccentric pin portion 102a becomes a boss 104b of the movable scroll 104.
Is accepted within. A slide bearing 103 for sliding with the outer peripheral surface of the slide bush 101 is provided on the inner peripheral surface of the boss 104b.

The end plate 104 of the movable scroll 104
a is provided with a spiral body 104c on the front surface thereof.
Discharge port 104d so as to penetrate from the front to the back of
Is provided. The discharge port 104d communicates with a discharge gas passage 102c provided in the crankshaft 102.

The slide bush 101 is, for example, shown in FIG.
As shown in (a) and (b), it has a cylindrical shape having a flange 101d on the oil supply passage 102b side.
The bottom surface of 1d has a concave portion 101a forming an oil pool portion. The recess 101a is configured to cover the opening of the oil supply passage 102b. Also this slide bush 1
A notch 101c is provided on the inner peripheral surface of 01 for smooth oil circulation.

The sliding bush 101 slides on the eccentric pin portion 102a to change the turning radius of the movable scroll 104, so that even if there is an error in processing and assembly, the tooth surface of the fixed scroll and the movable scroll 104 can be changed. It plays a role of making a turning motion by always contacting the tooth surface.

[0008]

However, in the above-described scroll compressor, the slide bush 101 has a flange portion 101d.
Is provided. The flange 101d is provided with a boss 104
Since it is necessary to extend to the outer peripheral side below b, the axial length of the slide bush 101 increases by the length of the flange portion 101d. For this reason, there was a problem that it was difficult to reduce the size of the compressor.

Further, since the flange 101d is provided, there is another problem that the number of processing steps is increased by the number of processing steps of the flange 101d.

It is therefore an object of the present invention to provide a scroll type fluid machine having a slide bush suitable for reducing the size of the apparatus and reducing the number of processing steps.

[0011]

According to a first aspect of the present invention, there is provided a scroll type fluid machine including a drive shaft, a movable scroll, and a slide bush. The drive shaft has an eccentric pin portion and has an oil supply passage that opens near the base of the eccentric pin portion. The movable scroll is provided so as to be able to revolve by a driving force of a driving shaft. The slide bush is loosely fitted to the eccentric pin portion and transmits the driving force of the drive shaft to the movable scroll. The slide bush has a cylindrical shape in which the outer diameter between both end surfaces is substantially uniform, and has a concave portion at the lower end surface that covers the opening of the oil supply passage and communicates with the inner peripheral surface of the slide bush.

According to the scroll type fluid machine of the first aspect, since the slide bush has a cylindrical shape in which the outer diameter between both end surfaces is substantially uniform, it does not have a flange portion. For this reason, the axial length of the slide bush can be reduced by the amount of the flange, and the fluid machine can be downsized accordingly.

Further, since there is no flange, processing for forming the flange is not required, and centerless processing is also possible, so that the number of processing steps can be reduced and the cost can be reduced.

In the scroll type fluid machine according to the second aspect, the outer peripheral surface of the slide bush is formed with oblique grooves reaching both end surfaces.

According to the scroll type fluid machine of the second aspect, the oil reaching the upper end surface of the slide bush can be drawn to the lower end surface side by viscous effect of the oblique groove. For this reason, it is possible to positively supply oil to the outer peripheral surface of the slide bush that slides on the bearing, and it is possible to secure an amount of oil necessary for lubrication.

In the scroll type fluid machine according to the third aspect, the concave portion has a crescent shape formed avoiding a portion where the oblique groove reaching the lower end surface is formed.

According to the scroll type fluid machine according to the third aspect, by forming the concave portion on the lower end surface avoiding the oblique groove, it is possible to prevent a decrease in the strength of the slide bush on the lower end surface, and to prevent chipping or chipping. Cracks can be prevented.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial cross-sectional view schematically showing a configuration of a scroll compressor according to Embodiment 1 of the present invention. Referring to FIG. 1, an eccentric pin portion 2a is formed at an upper end of a crankshaft 2 connected to a rotor (not shown) of a motor. The crankshaft 2 has an oil supply passage 2b
And a discharge gas passage 2c are provided in parallel with each other in the axial direction. The refueling passage 2b is formed without being separated, and opens near the base of the eccentric portion 2a. The discharge gas passage 2c reaches the end face of the eccentric pin 2a from below. A substantially cylindrical slide bush 1 is loosely fitted to the eccentric portion 2a of the crankshaft 2. The movable scroll 4 is supported so as to be able to revolve by receiving a rotational force from the crankshaft 2 via the slide bush 1.

The movable scroll 4 has a head plate 4a, a spiral body 4c projecting from the front surface of the head plate 4a, and a boss 4b projecting from the back surface of the head plate 4a. An eccentric pin portion 2a into which the slide bush 1 is loosely fitted is received in the boss portion 4b, and a slide bearing 3 that slides on the outer peripheral surface of the slide bush 1 is mounted on the inner peripheral surface of the boss portion 4b. Have been. The end plate 4a has a discharge port 4d penetrating from the front surface to the rear surface. The discharge port 4d communicates with the discharge gas passage 2c of the crankshaft 2.

The crankshaft 2 is rotatably supported by a rolling bearing 5 as an upper bearing and a lower bearing (not shown). The rolling bearing 5 has an inner ring and an outer ring that are arranged at an interval from each other, and a rolling element that is arranged to be able to roll between them.

The slide bush 1 is shown in FIG.
As shown in (b), the outer diameter from the upper end surface to the lower end surface has a substantially uniform cylindrical shape, and the flange portion 101 as shown in FIGS.
does not have d. Further, the slide bush 1 has a concave portion 1 a on the lower end surface, and the concave portion 1 a communicates with the inner peripheral surface of the slide bush 1. The inner peripheral surface of the slide bush 1 has a shape in which a notch 1c is provided in a part of the D-cut shape. On the outer peripheral surface of the slide bush 1,
An oblique groove 1b extending from the upper end surface to the lower end surface is provided.

The slide bush 1 has an eccentric pin 2a.
FIGS. 3 to 6 show a state in which it is loosely fitted.

FIG. 3 is a top view of a state in which the slide bush 1 is loosely fitted to the eccentric pin portion 2a.
FIG. 5 is a schematic sectional view taken along the line AA of FIG. 3, FIG. 5 is a view of the slide bush 1 loosely fitted to the eccentric portion 2a as viewed from below, and FIG. It is the side view seen from.

Referring to FIGS. 3 to 6, since notch 1c is provided on the inner peripheral surface of slide bush 1, even when slide bush 1 is loosely fitted to eccentric pin 2a, notch 1c is provided. Thereby, a large space can be created between the eccentric pin portion 2a and the outer peripheral surface. For this reason, the oil circulation described below can be performed smoothly.

As shown mainly in FIG. 5, the concave portion 1a provided on the lower surface of the slide bush 1 is formed in a crescent shape avoiding the region where the oblique groove 1b is formed, and the inner peripheral surface of the slide bush 1 is formed. And it is formed so that it may communicate with notch 1c. A concave portion 1a provided on the lower surface of the slide bush 1 is formed so as to cover an open end of an oil supply passage 2b provided on the crankshaft 2 as shown in FIG.

As shown mainly in FIG. 6, the oblique groove 1b is formed so as to be inclined upward with respect to the rotation direction of the crankshaft 2 (the direction of arrow C).

Next, the operation of the scroll compressor according to the present embodiment will be described. Referring to FIG. 1, first, the crankshaft 2 is rotationally driven by energizing the motor. This allows
The eccentric pin portion 2a eccentrically provided on the crankshaft 2 and the slide bush 1 loosely fitted therein revolve.
As a result, the orbiting scroll 4 revolves while maintaining its attitude relative to a fixed scroll (not shown).

Due to the revolution of the movable scroll 4, the compression chamber formed by the spirals 4c of the fixed scroll and the movable scroll 4 moves while gradually reducing the volume from the outer peripheral side to the inner peripheral side. Thereby, the refrigerant gas in the compression chamber is compressed and discharged from the discharge port 4d in the innermost peripheral region.

The discharged refrigerant gas is discharged into the casing below the crankshaft 2 through a discharge gas passage 2c provided in the crankshaft 2, and further discharged from the inside of the casing to the outside of the casing through a discharge pipe (not shown). You.

During this series of operations, the oil circulates as follows. First, oil is pumped upward from an oil reservoir at the bottom of the casing through an oil supply passage 2b by centrifugal force or a pump caused by rotation of the crankshaft 2. Refueling passage 2
b reaches the opening end of the slide bush 1 and fills the recess 1a provided in the slide bush 1.
And the eccentric portion 2a goes up. On this occasion,
Notch 1 mainly provided on the inner peripheral surface of slide bush 1
Most of the oil will go upward through c.

The oil reaching the upper end of the slide bush 1 is supplied to the sliding surface between the slide bush 1 and the slide bearing 3. At this time, the oil is forcibly drawn downward from above the sliding surface by viscous effect due to the lead angle of the oblique groove 1b provided on the outer peripheral surface of the slide bush 1.
Then, the oil drawn into the sliding surface spreads over the entire circumference of the sliding surface due to the rotation of the eccentric portion 2a. Then, the oil that has fallen down along the sliding surface lubricates between the inner and outer races of the bearing portion 5 and the rolling elements, and then returns to an oil reservoir at the bottom of the casing through an oil return hole and an oil return pipe provided in the housing. Return.

In this embodiment, the slide bush 1 has a cylindrical shape with a substantially uniform outer diameter from the upper end surface to the lower end surface, and does not have the flange portion 101d unlike the conventional example (FIG. 7). For this reason, the axial length of the slide bush 1 can be reduced by the amount of the flange portion 101d, and accordingly, the scroll compressor can be downsized.

More specifically, the size of the flange is about 3 mm. If the flange is eliminated, the balance weight for balancing the flange can be reduced, and the compressor can be synergistically reduced in size. Therefore, the size of the entire compressor can be reduced by about 5 mm.

Further, since there is no flange, processing for forming the flange is not required, and centerless processing is also possible, so that the number of processing steps can be reduced and the cost can be reduced.

Since the oblique groove 1b is provided on the outer peripheral surface of the slide bush 1, oil can be forcibly drawn from the upper end surface to the lower end surface side of the slide bush 1 by viscous effect of the oblique groove 1b. For this reason, it is possible to positively supply oil to the sliding portion between the outer peripheral surface of the slide bush 1 and the inner peripheral surface of the slide bearing 3, and it is easy to secure an amount of oil necessary for lubrication.

In order to forcibly extract the oil by the oblique groove 1b, the oblique groove 1b is provided so as to be inclined upward with respect to the rotation direction of the crankshaft 2 (the direction of arrow C) as shown in FIG. Need to be.

On the lower end surface of the slide bush 1, a concave portion 1a is formed in a crescent shape avoiding a portion where the oblique groove 1d is formed. For this reason, it is possible to prevent a decrease in the strength of the slide bush 1 at the lower end surface, and to prevent chipping or cracking.

Since the flange portion is not provided, the capacity of the concave portion 1a for storing oil is smaller than the case where the flange portion 101d is provided (FIGS. 7 and 8). For this reason, there is a concern that the amount of oil supplied to the sliding portion between the outer peripheral surface of the slide bush 1 and the inner peripheral surface of the slide bearing 3 may decrease. However, the amount of oil supplied to the sliding surface is determined by the amount of oil drawn out by the diagonal groove 1d. Since more oil can be stored in the recess 1a than the amount drawn out, even if there is no flange, the amount of oil Does not decrease.

In this embodiment, the scroll compressor has been described. However, the present invention is not limited to this, and may be applied to a scroll expander.

In the present embodiment, the recess 1a is formed in a crescent shape avoiding the portion where the oblique groove 1b is formed. However, if the lower end surface of the slide bush 1 can secure strength, The recess 1a may be provided over the entire circumference of the lower end surface.

Further, in the present embodiment, a case has been described in which the number of the oblique grooves 1b provided on the outer peripheral surface of the slide bush 1 is one. However, a plurality of the oblique grooves 1b may be provided depending on the design.

The crankshaft 2 of the slide bush 1
Is restricted by a forcing means such as a C-shaped retaining ring (not shown) fitted near the upper end of the eccentric pin portion 2a.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[0045]

According to the scroll-type fluid machine according to the first aspect, the slide bush has a cylindrical shape in which the outer diameter between both end surfaces is substantially uniform, and therefore does not have a flange portion. For this reason, the axial length of the slide bush can be reduced by the amount of the flange, and the fluid machine can be downsized accordingly.

Further, since there is no flange, processing for forming the flange is not required, and centerless processing is also possible, so that the number of processing steps can be reduced and the cost can be reduced.

In the scroll-type fluid machine according to the second aspect, the outer peripheral surface of the slide bush is formed with oblique grooves reaching both end surfaces. Thereby, the oil that has reached the upper end surface of the slide bush can be drawn out to the lower end surface side by viscous effect of the oblique groove. For this reason, it is possible to positively supply oil to the outer peripheral surface of the slide bush that slides on the bearing, and it is possible to secure an amount of oil necessary for lubrication.

In the scroll type fluid machine according to the third aspect, the concave portion has a crescent shape formed so as to avoid the portion where the oblique groove reaching the lower end surface is formed. Thereby, the strength of the slide bush at the lower end surface can be prevented from lowering, and chipping or cracking can be prevented.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view schematically showing a configuration of a scroll compressor according to an embodiment of the present invention.

FIG. 2 is an upper perspective view (a) and a lower perspective view (b) showing a configuration of a slide bush of the scroll compressor according to one embodiment of the present invention.

FIG. 3 is a top view showing a state in which a slide bush is loosely fitted to an eccentric portion.

FIG. 4 is a schematic sectional view taken along line AA of FIG. 3;

FIG. 5 is a bottom view showing a state in which the slide bush is loosely fitted to the eccentric portion.

FIG. 6 is a side view as viewed from a direction B in FIG. 3;

FIG. 7 is a partial cross-sectional view schematically showing a configuration of a conventional scroll compressor.

FIG. 8 is an upper perspective view (a) and a lower perspective view (b) of a slide bush of a conventional scroll compressor.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 slide bush 1a recess 1b oblique groove 2 crankshaft 2a eccentric pin 2b oil supply passage 4 movable scroll

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Shuichi Shiromura 3-12 Chikushinmachi, Sakai-shi, Osaka Daikin Industries, Ltd. Inside the coastal plant of Sakai Seisakusho Co., Ltd. No. 12 Daikin Industries, Ltd. Sakai Plant Rinkai Plant F-term (reference) 3H039 AA03 AA12 BB05 BB07 BB11 CC02 CC12 CC13 CC27 CC43 CC44

Claims (3)

[Claims] An oil supply passage (2) having an eccentric pin (2a) and opening near the base of the eccentric pin (2a).
b), a movable scroll (4) provided to be revolvable by the driving force of the drive shaft (2), and the drive shaft is loosely fitted to the eccentric pin portion (2a). A slide bush (1) for transmitting the driving force of (2) to the orbiting scroll (4), wherein the slide bush (1) has a cylindrical shape with an outer diameter between both end surfaces being substantially uniform. A scroll-type fluid machine that has a recess (1a) at the lower end surface that covers the opening of the oil supply passage (2b) and communicates with the inner peripheral surface of the slide bush (1). 2. The scroll type fluid machine according to claim 1, wherein an oblique groove (1b) reaching the both end surfaces is formed on an outer peripheral surface of the slide bush (1). 3. The scroll-type fluid according to claim 2, wherein the concave portion (1a) has a crescent shape formed avoiding a portion where the oblique groove (1b) reaches the lower end surface. machine.