JP2017180407A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cooling characteristics of a drive bearing placed between a crank pin of a crank shaft and a revolving boss part formed at a rear surface of a revolving scroll together with a drive bush.SOLUTION: A scroll compressor comprises a closed housing; a scroll compression mechanism; an electric motor; a crank shaft rotationally driven by the electric motor; a crank pin 11A arranged at the upper end of the crank shaft and inserted into a revolving boss part of a revolving scroll through the drive bushing 25 and a drive bearing 26 in a relative rotatable manner; an oil supply passage formed along an axis line of the crank shaft; and open hole oil passage holes 25a formed in the inside of a cylindrical wall surface of the drive bushing 25 along an axial direction. The oil passage holes 25a are formed at a prescribed load angle region θ where an outer peripheral surface of the drive bushing 25 is press-contacted against an inner peripheral surface of the drive bearing 26 when the scroll compressor is operated under a certain load.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a scroll compressor that improves the cooling performance of a drive bearing interposed with a drive bush between a crankpin of a crankshaft that drives the orbiting scroll and an orbiting boss formed on the back surface of the orbiting scroll. It is about.

  As disclosed in Patent Document 1, in a scroll compressor, a drive bush is rotatably fitted in a revolving boss formed on the back surface of an end plate of a revolving scroll, and a slide groove formed in the drive bush A crank pin of the crank shaft is slidably fitted therein, and at least one through hole is formed in the drive bush along the axial direction, and a radial groove communicating with the through hole is formed. There is something.

  According to the above configuration, the lubricating oil sealed in the scroll compressor and the gas containing the mist of the lubricating oil are allowed to flow through the through hole and groove to cool the drive bush, and at the same time, the end face of the drive bush and the end face of the rotary shaft are reduced. Can be well lubricated.

Japanese Utility Model Publication No. 4-49684

  However, in the above configuration, the position of the through hole drilled in the drive bush is not necessarily optimized. That is, in a scroll compressor in which the crankshaft is arranged in the vertical direction, lubricating oil is supplied from an oil pump at the lower end of the crankshaft through an oil supply passage formed along the axis of the crankshaft. The oil is discharged from the upper end of the crankshaft and flows back to the oil pump through the gap of the drive bearing, but this lubricating oil has a gap between the drive bearing and the drive bush on the non-load side where the gap becomes large. From the gap between the drive bush and the crankpin, most of the amount is recirculated, and the amount of lubricating oil passing through the load side where the gap becomes smaller is reduced.

  In this way, the amount of lubricating oil that passes through the portion of the drive bearing where the load from the crank pin acts strongly decreases, so that the exhaust heat of the drive bearing is difficult to promote and the drive bearing is damaged, such as early wear. There is. In particular, during low-speed operation, the amount of lubricating oil drawn through the crankshaft is reduced, so that it is difficult to form an oil film, and this problem becomes significant.

  The present invention has been made to solve the above-described problems, and is interposed together with a drive bush between a crankpin of a crankshaft that drives the orbiting scroll and an orbiting boss formed on the back surface of the orbiting scroll. It is an object of the present invention to provide a scroll compressor capable of improving the cooling performance of a drive bearing.

In order to solve the above problems, the present invention employs the following means.
That is, the scroll compressor according to the present invention includes a hermetic housing, a scroll compression mechanism that is installed in an upper part of the hermetic housing in combination of a fixed scroll and an orbiting scroll, and a lower part of the scroll compression mechanism. An electric motor, a crankshaft that is rotationally driven by the electric motor, and a swivel boss provided on the upper end of the crankshaft and formed on the back surface of the orbiting scroll via a cylindrical drive bush and a drive bearing A crank pin that is inserted into the shaft so as to be relatively rotatable, an oil supply passage that is formed along the axial center line of the crank shaft, and that supplies lubricating oil to the vicinity of the drive bearing; and an axial direction inside the cylindrical wall surface of the drive bush A through-hole-shaped oil passage hole formed along the drive hole, and the oil passage hole is configured to drive the drive bush during load operation. The outer peripheral surface is formed in a predetermined load angle region is pressed against the inner peripheral surface of the drive bearing of the.

  During the load operation of the scroll compressor having the above-described configuration, the outer peripheral surface of the drive bush is pressed against the inner peripheral surface of the drive bearing under pressure from the crank pin, so that the outer peripheral surface of the crank pin and the inner surface of the drive bush are A predetermined load angle region is generated in which the gap between the peripheral surface and the gap between the outer peripheral surface of the drive bush and the inner peripheral surface of the drive bearing is reduced. Therefore, it is difficult for the lubricating oil supplied to the vicinity of the drive bearing from the oil supply passage formed along the axis of the crankshaft to pass through the range corresponding to the load angle region in the gap. Thus, the amount of lubricating oil recirculated in this region decreases.

  However, since the lubricating oil can recirculate downward through a through-hole-like oil passage hole formed in the drive bush adjacent to this load angle region, the drive bushing is caused by the lubricating oil passing through this oil passage hole. And the exhaust heat of the drive bearing adjacent to the drive bush is promoted. Accordingly, it is possible to prevent damage such as early wear in a portion corresponding to the load angle region of the drive bearing.

The said structure WHEREIN: It is preferable to form the said oil passage hole in multiple numbers along with the circumferential direction of the said drive bush. By providing a plurality of oil passage holes in this manner, the oil passage holes can exist over the entire range of the load angle region extending in the circumferential direction of the drive bush, and the cooling effect of the drive bush can be enhanced.
Moreover, since the inner diameter of each oil passage hole can be reduced, it is possible to avoid a decrease in the strength of the drive bush due to the formation of the oil passage hole.

  As described above, according to the scroll compressor according to the present invention, the drive interposed together with the drive bush between the crank pin of the crankshaft that drives the orbiting scroll and the orbiting boss portion formed on the back surface of the orbiting scroll. The cooling performance of the bearing can be improved.

It is a longitudinal cross-sectional view which shows an example of the scroll compressor which can apply this invention. FIG. 2 is an enlarged longitudinal sectional view of the drive bush shown in FIG. 1. It is a top view of the drive bush which shows one Embodiment of this invention by the III arrow view of FIG.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view of the entire scroll compressor according to an embodiment of the present invention. In this embodiment, an example of a hermetic electric scroll compressor will be described. However, the present invention is not limited to this, and can be applied to an open type.
The scroll compressor 1 includes a cylindrical bottomed steel plate sealed housing 2 that is long in the vertical direction. A scroll compression mechanism 3 is installed in an upper part of the hermetic housing 2, and an electric motor 4 is installed in a lower part thereof.

  In the hermetic housing 2, the upper side of the scroll compression mechanism 3 is a discharge chamber 5 into which high-pressure gas compressed by the scroll compression mechanism 3 is discharged, and a discharge pipe 6 is connected thereto. The lower side of the scroll compression mechanism 3 is a suction chamber 7 into which low-pressure suction gas is sucked, and a suction pipe 8 is connected thereto. On the suction chamber 7 side, an electric motor 4 composed of a stator 9 and a rotor 10 is installed in the hermetic housing 2 by press fitting or the like, and is coupled to the rotor 10 of the electric motor 4 to be connected to the electric motor. A crankshaft 11 that is rotationally driven by 4 is extended in the vertical direction.

  The lower end portion of the crankshaft 11 is supported by a lower bearing 12 provided in the hermetic housing 2, and a known oil pump 13 provided between the lower end portion and the lower bearing 12 is used. The lubricating oil 14 stored in the bottom of the hermetic housing 2 is passed through the oil supply passage 11a formed along the axial direction in the crankshaft 11, and the scroll compression mechanism 3 and the upper bearing member 15, the drive bearing 26 described later, etc. The main lubrication parts are supplied with oil and the parts can be lubricated. The oil supply passage 11 a opens at the upper end of the crankshaft 11.

  The scroll compression mechanism 3 is installed in the sealed housing 2 via the upper bearing member 15. The scroll compression mechanism 3 includes a fixed scroll 16 that is fixedly installed on the upper bearing member 15 and a orbiting scroll 20 that is supported on the upper bearing member 15 so as to be capable of revolving around the fixed scroll 16. The fixed scroll 16 includes a fixed end plate 17 and a fixed spiral wrap 18 standing on one surface thereof, and a discharge port 19 is provided at the center of the fixed end plate 17. .

  The orbiting scroll 20 includes an orbiting end plate 21 and an orbiting spiral wrap 22 standing on one surface thereof, and a cylindrical orbiting boss portion 23 is integrally formed on the back side of the orbiting end plate 21. It is configured. In the fixed scroll 16 and the orbiting scroll 20, the fixed spiral wrap 18 and the orbiting spiral wrap 22 are 180 degrees out of phase and meshed in a known manner, whereby a pair of compression chambers 24 are interposed between the scrolls 16 and 20. Is to be formed. The pair of compression chambers 24 are configured to move while the volume is reduced from the outer peripheral position to the center portion when the orbiting scroll 20 is revolving orbited, and to perform a compression action.

  In the orbiting scroll 20, the back surface of the orbiting end plate 21 is supported on the thrust bearing portion 15 </ b> A of the upper bearing member 15, and the crank pin 11 </ b> A provided at the upper end of the crankshaft 11 is provided on the orbiting boss portion 23 on the back surface side. A structure capable of revolving orbiting around the fixed scroll 16 so that the orbiting radius can be varied by being inserted in a relatively rotatable manner via a drive bush 25 and a drive bearing 26 constituting a known driven crank mechanism. It is said that. Reference numeral 25 </ b> W is a balancer weight provided integrally with the drive bush 25. Between the back surface of the orbiting end plate 21 of the orbiting scroll 20 and the thrust bearing portion 15 </ b> A of the upper bearing member 15, an anti-rotation means 27 including an Oldham ring or the like for preventing the orbiting scroll 20 from rotating is incorporated.

  The upper portion of the crankshaft 11 is rotatably supported by the journal bearing portion 15B of the upper bearing member 15. The fixed end plate 17 of the fixed scroll 16 is provided with a discharge cover 28 on the back side thereof and a reed valve type discharge valve 29 for opening and closing the discharge port 19. Furthermore, the fixed end plate 17 of the fixed scroll 16 has a plurality of different swirl angle positions along the spiral direction of the fixed spiral wrap 18 on the outer peripheral side with respect to the discharge port 19 provided in the center. A plurality of pairs of relief ports 30 composed of a plurality of hole groups communicating the compression chamber 24 and the discharge chamber 5 and relief valves 31 for opening and closing the ports 30 are provided.

  As described above, the lubricating oil 14 supplied to the scroll compression mechanism 3 and the like through the oil supply passage 11a formed in the crankshaft 11 is supplied to the drive bush 25, the drive bearing 26, the thrust bearing portion 15A, and the like. As the drive bearing 26, a sliding bearing is selected instead of a rolling bearing because of the fact that the lubricating oil 14 can be supplied in this way and the spatial relationship.

  FIG. 2 is an enlarged longitudinal sectional view of the drive bush 25, and FIG. 3 is a plan view of the drive bush 25 as viewed in the direction of arrow III in FIG. As shown here, the drive bush 25 formed in a cylindrical shape is formed with a plurality of through-hole-shaped oil passage holes 25a along the axial direction inside the cylindrical wall surface. The oil passage holes 25a are, for example, three round holes, but the hole shape and quantity are not limited to this, and may be other hole shapes, or may be single or more than four. It is also possible to do. Further, if the strength of the drive bush 25 permits, the communication hole 25a may be formed in a curved long hole shape extending in the circumferential direction of the drive bush 25 or the like.

  As shown in FIG. 3, the oil passage hole 25 a has an outer peripheral surface of the drive bush 25 that receives pressure from the crankpin 11 </ b> A of the crankshaft 11 and is pressed radially outward during the load operation of the scroll compressor 1. It is formed in accordance with a predetermined load angle region θ that is pressed against the inner peripheral surface of the drive bearing 26. The angle of the load angle region θ is approximately 60 to 80 degrees. The oil passage hole 25a may be formed over a slightly wider range.

  During the load operation of the scroll compressor 1, the crank pin 11A is slightly decentered with respect to the inner peripheral surface of the drive bush 25, and a gap S1 between the outer peripheral surface of the crank pin 11A and the inner peripheral surface of the drive bush 25 is It becomes larger in the region opposite to the load angle region θ. Similarly, the gap S2 between the outer peripheral surface of the drive bush 25 and the inner peripheral surface of the drive bearing 26 is also increased. It is desirable that the oil passage hole 25a is approximately 180 degrees opposite to the maximum width position of the gaps S1 and S2.

  During the load operation of the scroll compressor 1 configured as described above, the outer peripheral surface of the crank pin 11A is pressed against the inner peripheral surface of the drive bush 25, and the outer peripheral surface of the drive bush 25 is pressed against the inner peripheral surface of the drive bearing 26. As a result, the clearance S1 between the outer peripheral surface of the crankpin 11A and the inner peripheral surface of the drive bush 25 and the clearance S2 between the outer peripheral surface of the drive bush 25 and the inner peripheral surface of the drive bearing 26 are reduced. A predetermined load angle region θ is generated. Therefore, the lubricating oil 14 supplied to the vicinity of the drive bearing 26 from the oil supply passage 11a formed along the axis of the crankshaft 11 passes through a range corresponding to the load angle region θ in the gaps S1 and S2. As a result, it becomes difficult to recirculate, and the recirculation amount of the lubricating oil 14 in this region decreases.

  However, since the lubricating oil 14 can return downward through the three through-hole-like oil passage holes 25a formed in the drive bush 25 adjacent to the load angle region θ, the oil passage holes 25a The drive bush 25 is cooled by the passing lubricating oil 14, and the exhaust heat of the drive bearing 26 adjacent to the drive bush 25 is promoted. Accordingly, it is possible to prevent damage such as premature wear in a portion corresponding to the load angle region θ of the drive bearing 26. This is particularly effective when the drive bearing 26 is a sliding bearing as in this embodiment. On the other hand, since the gaps S1 and S2 widen on the non-load side, a large amount of the lubricating oil 14 is recirculated from here. Therefore, the drive bush 25 is cooled over the entire circumference.

  Since the plurality of oil passage holes 25a are formed side by side in the circumferential direction of the drive bush 25, the oil passage holes 25a are provided over the entire range of the load angle region θ extending in the circumferential direction of the drive bush 25. The cooling effect of the drive bush 25 can be enhanced. Moreover, since the inner diameter of each oil passage hole 25a can be reduced, it is possible to avoid a decrease in strength of the drive bush 25 due to the formation of the oil passage hole 25a.

  As described above, according to the scroll compressor 1 according to the above embodiment, the crankpin 11A of the crankshaft 11 that drives the orbiting scroll 20 and the orbiting boss portion 23 formed on the back surface of the orbiting scroll 20 are provided. It is possible to improve the cooling performance of the drive bearing 26 interposed with the drive bush 25 therebetween, and to avoid damage to the drive bearing 26.

  It should be noted that the present invention is not limited to the configuration of the above-described embodiment, and can be appropriately modified or improved within a scope not departing from the gist of the present invention. Are also included in the scope of rights of the present invention.

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Sealed housing 3 Scroll compression mechanism 4 Electric motor 10 Rotor 11 Crankshaft 11A Crankpin 11a Oil supply passage 14 Lubricating oil 16 Fixed scroll 20 Orbiting scroll 23 Orbiting boss part 25 Drive bush 25a Oil passage hole 26 Drive bearing θ Load angle region S1 Clearance between crankpin and drive bush S2 Clearance between drive bush and drive bearing

Claims (2)

A sealed housing;
A scroll compression mechanism in which a fixed scroll and a turning scroll are combined and installed at an upper part in the sealed housing;
An electric motor installed in a lower part of the scroll compression mechanism;
A crankshaft that is rotationally driven by the electric motor;
A crank pin that is provided at the upper end of the crankshaft and is inserted into a revolving boss portion formed on the back surface of the orbiting scroll via a cylindrical drive bush and a drive bearing;
An oil supply passage formed along the axis of the crankshaft and supplying lubricating oil to the vicinity of the drive bearing;
A through-hole-shaped oil passage hole formed along the axial direction inside the cylindrical wall surface of the drive bush;
Comprising
The oil passage hole is a scroll compressor formed in a predetermined load angle region in which an outer peripheral surface of the drive bush is pressed against an inner peripheral surface of the drive bearing during load operation.   The scroll compressor according to claim 1, wherein a plurality of the oil passage holes are formed side by side in a circumferential direction of the drive bush.

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