JP2013002350A - Scroll compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll compressor in which rigidity of a drive shaft and an oil supply amount of main and sub bearings are secured and besides, oil loss amount is reduced.SOLUTION: There is provided the scroll compressor which has a compression chamber formed from an orbiting scroll and a fixed scroll, and which compresses a refrigerant by changing the volume of the compression chamber with rotation of the drive shaft. The scroll compressor includes a route in which an oil supplied to an orbiting back chamber that is formed from the back of the orbiting scroll and an end face of the drive shaft, then used for lubricating a main bearing, is used for lubricating the sub bearing and then returned to an oil reservoir.

Description

  The present invention relates to a scroll compressor, and more particularly to a scroll compressor provided with an oil drain pipe that guides oil that has lubricated a bearing.

  As a background art of this technical field, there is one disclosed in Patent Document 1.

  The scroll fluid machine accommodates a compression part that forms a working chamber by meshing a fixed scroll and an orbiting scroll each provided with a spiral wrap on each end plate, a motor including a stator and a rotor, and a compression part and the motor. A sealed casing, a drive shaft that has an oil supply passage and an oil discharge passage inside, transmits the rotational force of the rotor to the compression portion, and a main bearing that supports the drive shaft on the compression portion side of the motor And an oil supply mechanism for supplying the lubricating oil stored in the sealed casing to the sliding portion of the drive shaft through the oil supply passage of the drive shaft.

  In this scroll fluid machine, the lubricating oil supplied by the oil supply mechanism installed at the lower end of the drive shaft is supplied to the swivel bearing through an oil supply passage provided in the drive shaft.

  A part of the lubricating oil that lubricates the orbiting bearing is supplied to the thrust support surface of the orbiting scroll, and a part of the lubricating oil that lubricates the orbiting bearing passes through the main bearing portion from the side surface of the frame above the motor. After being discharged into the space and lubricating the main bearing portion, a portion of the lubricating oil is guided to the oil discharge passage in the drive shaft and discharged into the space below the motor.

JP 2009-127614 A

  In Patent Document 1, since the oil supply passage and the oil discharge passage are formed inside the drive shaft, in order to secure the amount of oil supply to the main bearing and the sub-bearing, the flow passage areas of the oil supply passage and the oil discharge passage are set. It needs to be bigger. The method of increasing the flow path area is difficult to adopt because the rigidity of the drive shaft is reduced. That is, it is difficult to secure the amount of oil supply while securing the rigidity with the configuration as it is.

  Further, in Patent Document 1, since the lubricating oil that has lubricated the main bearing and the slewing bearing is discharged from the internal oil discharge passage of the drive shaft to the space below the motor, the lubricating oil discharged from the rotating drive shaft is removed. The mixture is agitated into a mist, mixed with the discharge gas in the hermetic casing and discharged to the outside of the compressor, which may increase the amount of oil rising.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a scroll compressor that can reduce the amount of oil rising while ensuring the steel properties of a drive shaft and the oil supply amounts of a main bearing and a sub-bearing.

The object of the present invention is as follows.
In the scroll compressor that forms a compression chamber with the orbiting scroll and the fixed scroll, and compresses the refrigerant by changing the volume of the compression chamber by rotation of the drive shaft,
The oil used to lubricate the main bearing after being supplied to the orbiting back chamber formed by the rear surface of the orbiting scroll and the end surface of the drive shaft is used to lubricate the sub bearing, and then to the oil reservoir. This is accomplished by a scroll compressor having a return path.

The object of the present invention is as follows.
In a sealed container,
A compression mechanism in which a compression chamber is formed by combining a fixed scroll and a turning scroll;
An electric motor that drives the compression mechanism;
A drive shaft connecting a crank part to the orbiting scroll;
A main bearing that supports the drive shaft;
A secondary bearing for supporting the drive shaft;
An oil absorption mechanism disposed at the end of the drive shaft on the auxiliary bearing side,
In the scroll compressor, the lubricating oil is supplied to the main bearing through an oil supply hole provided in the drive shaft, and the lubricating oil is supplied to the auxiliary bearing through the first drain oil pipe.
This is achieved by a scroll compressor in which a second drain oil pipe that guides oil from the first oil drain pipe to the auxiliary bearing is connected to the first oil drain pipe.

  ADVANTAGE OF THE INVENTION According to this invention, oil amount can be reduced, ensuring the steel nature of a drive shaft, and the oil supply amount of a main bearing and a subbearing.

Sectional drawing 1 of the scroll compressor of 1st Embodiment of this invention. Sectional drawing 2 of the scroll compressor of 1st Embodiment of this invention. Sectional drawing of the single-state state of the 2nd oil draining pipe used for the scroll compressor of FIG. 1 and FIG. Assembly explanatory drawing of the 2nd oil draining pipe used for the scroll compressor of FIG. 1 and FIG. Sectional drawing 1 of the scroll compressor of 2nd Embodiment of this invention. Sectional drawing 2 of the scroll compressor of 2nd Embodiment of this invention. Sectional drawing of the single-piece | unit state of the 2nd drainage pipe used for the scroll compressor of FIG. 5 and FIG. The assembly explanatory drawing of the 2nd oil draining pipe used for the scroll compressor of Drawing 5 and Drawing 6. Sectional drawing of the scroll compressor of 3rd Embodiment of this invention. Sectional drawing of the single-piece | unit state of the 2nd oil draining pipe used for the scroll compressor of FIG. Explanatory drawing of the outer peripheral part of the stator of FIG.1, FIG.2 and FIG.5, FIG.6 and FIG.

  Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. The same reference numerals in the drawings of the respective embodiments indicate the same or equivalent. However, the present invention is not limited to the following embodiments. In addition, unless otherwise specified, the scope of the present invention is not intended to limit the scope of the present invention only to those embodiments, but is merely an illustrative example.

  The overall structure of the scroll compressor 1 of this embodiment will be described with reference to FIG. The scroll compressor 1 is configured by housing a compression mechanism 2, an electric motor 3, a sub-bearing portion 4, and an oil supply mechanism in an airtight container 100. In this embodiment, it is a vertical scroll compressor in which the compression mechanism 2 and the electric motor 3 are vertically arranged.

  The hermetic container 100 is configured by covering the end plate 101 and the end plate 102 having the same shape on the outside of the body 103. As a result, a large gap 104 between the outer diameter of the fixed scroll 6 and the inner diameter of the end plate 101 is ensured. An oil sump 82 for storing oil is provided at the bottom of the sealed container 100.

  The compression mechanism 2 includes an orbiting scroll 5, a fixed scroll 6, a frame 7, a drive shaft 8, a main bearing 63, an orbiting bearing 13, and an orbiting mechanism 9. The compression mechanism 2 forms a compression chamber 81 by combining the spiral wrap 15 of the fixed scroll 6 and the spiral wrap 11 of the orbiting scroll 5.

  The orbiting scroll 5 includes a spiral wrap 11, an end plate 10, and a shaft support portion (boss portion) 5a. The wrap 11 is erected vertically on one side of the end plate 10. The shaft support portion 5a is formed so as to protrude perpendicularly to the other side (the opposite wrap side) of the end plate 10. On the back side of the end plate 10 of the orbiting scroll 5, an orbiting mechanism 9 and an orbiting bearing 13 into which the crank portion 12 of the drive shaft 8 is inserted are provided. The turning mechanism 9 includes an Oldham key and a keyway. The slewing bearing 13 is provided in the shaft support portion 5a.

  The fixed scroll 6 includes a spiral wrap 15, an end plate 14, a suction port 16, and a discharge port 17, and is fixed to the frame 7 via bolts 92. Thus, the orbiting scroll 5 is sandwiched between the fixed scroll 6 and the frame 7 so as to be capable of orbiting. The fixed scroll 6 has a spiral wrap 15 standing upright on the end plate 14, a suction port 16 is provided in the outer peripheral portion, and a discharge port 17 is provided in the center portion of the end plate. The wrap 15 is erected vertically on one side of the end plate 14. A suction pipe 85 provided in the sealed container 100 is connected to the suction port 16 of the fixed scroll 6. Further, the sealed container 100 is provided with a discharge pipe 22 that communicates with the space between the frame 7 and the electric motor 3.

  The outer periphery of the frame 7 is fixed to the sealed container 100, and the main bearing 63 is supported at the center thereof. The main bearing 63 is covered with a frame seal 84. The frame seal 84 is detachably attached to the frame 7 so as to hold the main bearing 63 from below. The main bearing 63 is provided between the electric motor 3 and the orbiting scroll 5.

  The drive shaft 8 has a crank portion 12 at the upper portion of the main shaft portion, and drives the orbiting scroll 5 by connecting the crank portion 12 to the orbiting scroll 5. The crank portion 12 is inserted into the swivel bearing 13 and is pivotally supported.

  The electric motor 3 constitutes a rotational drive means for driving the compression mechanism 2 via the drive shaft 8 and has a stator 18 and a rotor 19 as basic elements. The stator 18 is attached to the sealed container 100. The outer peripheral surface of the stator 18 is formed in close contact with the inner surface of the sealed container 100. And the notch 18b is formed in several places (4 places in this embodiment) of the outer peripheral surface of the stator 18 (refer FIG. 11), and the space | gap 72 is formed between the airtight containers 100 by this notch 18b. Is done. The gap 72 is provided to allow the refrigerant gas discharged from the discharge port 17 to pass therethrough and to cool the electric motor 3. The rotor 19 is fastened to the main shaft portion of the drive shaft 8.

  The sub bearing portion 4 is provided so as to support the drive shaft 8 on the side opposite to the compression mechanism when viewed from the electric motor 3. The sub bearing portion 4 includes a sub bearing 51, a sub bearing housing 52 in which the sub bearing 51 is inserted, and a lower frame 53 fastened to the sub bearing housing 52. The lower frame 53 is fixed to the sealed container 100. Thus, the drive shaft 8 is pivotally supported on both sides of the electric motor 3 by the main bearing 63 and the auxiliary bearing 51, and the crank portion 12 at the upper end is pivotally supported by the swing bearing 13.

  When the drive shaft 8 is rotated by the rotation of the electric motor 3, the orbiting scroll 5 performs the orbiting motion with respect to the fixed scroll 6 while maintaining the posture by the function of the orbiting mechanism 9. A balance weight 20 is attached between the rotor 19 and the orbiting scroll 5 and a rotor balance weight 21 is attached to the rotor 19 in order to cancel out the unbalanced force generated by the orbiting motion.

  The compression chamber 81 configured by meshing the fixed scroll 6 and the orbiting scroll 5 is subjected to a compression operation in which the volume thereof is reduced by the orbiting movement of the orbiting scroll 5. In this compression operation, the working fluid is sucked into the compression chamber 81 from the suction port 16 along with the turning motion of the orbiting scroll 5, and the sucked working fluid passes through the compression stroke from the discharge port 17 of the fixed scroll 6 to the sealed container 100. It is discharged into the discharge space inside. That is, the space in the sealed container 100 is maintained at the discharge pressure. This compressor is a so-called high pressure chamber type. Further, the working fluid in the sealed container 100 is discharged from the discharge pipe 22.

  The oil supply mechanism includes an oil supply pump 83, an oil supply hole 61 in the drive shaft 8, a first oil discharge pipe 60, and a second oil discharge pipe 66.

  The oil supply pump 83 is attached to the lower end of the drive shaft 8 and is provided for supplying the lubricating oil stored in the oil sump 82 through the oil supply hole 61 to the slewing bearing 13 and the main bearing 63 for lubrication. Yes. An oil supply pump 83 shown in FIG. 1 is an example of a positive displacement pump 105. As another example, FIG. 2 shows a structure when the centrifugal pump 106 is employed. The oil supplied to the oil supply hole 61 is supplied to a compression chamber or the like via a back pressure control valve (not shown), and is also supplied to the sliding portion between the orbiting scroll 5 and the fixed scroll 6.

  The oil supply hole 61 is provided concentrically with the axis of the drive shaft 8 shown in FIG. As another example, FIG. 2 shows a structure having an upper oil supply passage 64b that is eccentric with respect to the axis of the drive shaft 8 and a lower oil supply passage 64a that is concentric.

  The first oil draining pipe 60 is manufactured in an L shape with a pipe-like hollow member, and is disposed in a horizontal portion 60 a fixed to the frame 7 and a recess 18 a (see FIG. 11) on the outer periphery of the stator 18 of the electric motor 3. It is comprised from the perpendicular | vertical part 60b.

  Next, fastening of the first oil drain pipe 60, the auxiliary bearing housing 52, and the second oil drain pipe 66 will be described with reference to FIG.

  The lower end portion 60 c of the drain oil pipe is fastened to the expanded portion of the upper end 66 a of the second drain oil pipe 66, and the lower end 66 b of the second oil drain pipe 66 is connected to the oil supply hole 52 a of the auxiliary bearing housing 52. The oil supply hole 52 a of the auxiliary bearing housing 52 is provided in the auxiliary bearing portion 4, and the oil that has flowed continuously here lubricates the auxiliary bearing 51.

  Here, the flow of the gap 104 will be described. The flow of the gap 104 during the operation of the scroll compressor 1 is indicated by arrows in FIGS.

  The oil supplied to the slewing bearing 13 and the main bearing 63 through the oil supply hole 61 inside the drive shaft 8 is guided into the horizontal portion 60a of the first oil drain pipe 60, and further passes through the vertical portion 60b. The oil is guided into the horizontal portion of the second oil drain pipe 66, passes through the sub bearing 4, and is returned from the lower end 4a of the sub bearing 4 to an oil sump 82 formed at the bottom of the hermetic container.

  Here, consider the conventional oil supply passage shown in broken lines in FIG. This is not a passage that the scroll compressor of FIG. 1 has, but is a virtual virtual oil supply passage 96 in FIG. Conventionally, there has been known a technique in which an oil supply passage perpendicular to the drive shaft 8 is provided in this way, and the auxiliary bearing is lubricated by branching from the oil supply hole 61. The same technique may be applied to the main bearing.

  However, it is conceivable that the pressure of the oil supplied to the swivel back chamber 95 is reduced.

  Here, if the high-pressure oil is supplied to the swivel back chamber 95 without branching, the high-pressure oil can be supplied to the back pressure chamber 97, and further to the end of the compressor that requires oil. Oil can be supplied.

  In this way, all the oil that has entered the oil supply hole 61 is used for lubrication of the slewing bearing 13 without branching, and most of it is used for lubrication of the main bearing 63 and further used for lubrication of the sub-bearing 51. Thus, each part is sufficiently lubricated, and the oil used for lubricating the auxiliary bearing 51 is returned to the oil sump 82 as it is, so that the amount of oil rising can be reduced.

  Next, a second embodiment of the present invention will be described with reference to FIGS.

  5 and 6 are sectional views of a scroll compressor according to the second embodiment of the present invention, and FIGS. 7 and 8 are sectional views and assembly explanatory views of a second oil draining pipe 66 used in the scroll compressor. The second embodiment is different from the first embodiment in the points described below, and the other points are basically the same as those in the first embodiment, and thus redundant description is omitted.

  In the second embodiment, the second oil draining pipe 66 is manufactured in a U-shape with one pipe-shaped hollow member (FIG. 7), and the U-shaped one end 66a is connected to the lower end 60c of the first oil draining pipe. The one end 66b is connected to the auxiliary bearing housing oil supply hole 52a. The oil supply hole 52a of the sub-bearing housing 52 is provided in the sub-bearing portion 4, and the oil flowing therethrough lubricates the sub-bearing 51 (see FIG. 6).

  Here, the flow of the gap 104 will be described. The flow of the gap 104 during the operation of the scroll compressor 1 is indicated by arrows in FIGS.

  According to the second embodiment, the second oil drain pipe 66 can be installed below the lower frame 53 (FIG. 8), and at the same time, fastened to the first oil drain pipe 60 and the auxiliary bearing housing 52. be able to. Since the oil supplied to the sub bearing 51 is lifted from the U-shaped bottom of the second drain oil pipe, the oil can be continuously supplied to the sub bearing 51 in any case. In addition, the oil passage can be made simpler and workability can be improved.

  Next, a third embodiment of the present invention will be described with reference to FIG.

  FIG. 9 is a cross-sectional view of a scroll compressor according to a third embodiment of the present invention, and FIG. 10 is a cross-sectional view of a second oil drain pipe 66 used in the scroll compressor. This third embodiment is different from the first and second embodiments in the following points, and the other points are basically the same as those in the first and second embodiments, and thus overlap. Description is omitted.

  In the third embodiment, the second oil draining pipe 66 is manufactured by a single pipe-shaped hollow member (FIG. 10), the upper end 66a is fastened to the first oil draining pipe 60, and the lower end is divided into two. The lower end oil supply portion 66 b at one end is fastened to the auxiliary bearing housing oil supply hole 52 a, and the lower end oil discharge portion 66 c at the other end is arranged below the lower frame 53 so as to be connected to the oil sump 82.

  Furthermore, the pipe diameter of the lower end oil drain part 66c of the second oil drain pipe 66 is configured to be narrower than the pipe diameters of the upper end part 66a and the lower end oil supply part 66b.

  Here, the flow of the gap 104 will be described. The flow of the gap 104 during operation of the scroll compressor 1 is indicated by arrows in FIG.

  The pipe diameter of the oil draining part 66c at the lower end of the second oil draining pipe 66 is made smaller than the pipe diameters of the upper end part 66a and the lower end oiling part 66b. It is branched by the second oil drain pipe 66, and a part of the gap 104 is lubricated to the auxiliary bearing 4 and discharged from the lower end of the auxiliary bearing 4, and a part is directly formed at the bottom of the sealed container. The oil sump 82 is returned.

  According to the third embodiment, with this configuration, the amount of oil supplied to the auxiliary bearing 4 does not become excessive, and an increase in input due to oil agitation in the auxiliary bearing 51 can be reduced.

  As described above, according to each embodiment, the lubrication amount of the main bearing and the sub-bearing is ensured with a simple configuration without impairing the steel properties of the drive shaft, and the life of the bearing is increased. The amount of ascent can be reduced and the life of the scroll compressor can be extended.

DESCRIPTION OF SYMBOLS 1 Scroll compressor 2 Compression mechanism 3 Electric motor 4 Sub bearing part 5 Orbiting scroll 5a Shaft support part 6 Fixed scroll 7 Frame 8 Drive shaft 9 Orbiting mechanism 10, 14, 101, 102 End plate 11, 15 Lap 12 Crank part 13, 62 Orbit Bearing 16 Suction port 17 Discharge port 18 Stator 18a, 71 Recess 18b Notch 18c End coil part 19 Rotor 20 Balance weight 21 Rotor balance weight 22 Discharge pipe 51 Sub bearing 51a Sub bearing oil drain part 52 Sub bearing housing 52a Sub bearing housing oil supply Hole 53 Lower frame 54 Balance weight cover 60 First oil pipe 60a First oil pipe horizontal part 60b First oil pipe vertical part 60c First oil pipe lower end 61 Oil hole 61a Oil hole upper part 61b Oil hole lower part 63 Main Bearing 64 Oil passage 64a Lower oil supply passage 64b Oil supply passage 65 Pipe presser 66 Second oil drain pipe 66a Second oil exhaust pipe upper end 66b Second oil exhaust pipe lower end oil supply section 66c Second oil exhaust pipe lower end oil exhaust section 81 Compression chamber 82 Oil reservoir 83 Oil pump 84 Frame seal 85 Suction pipe 90 Magnet 91 Pipe 92 Bolt 93 Seal ring 94 Oil supply pocket 95 Revolving back chamber 96 Virtual oil supply passage 97 Back pressure chamber 100 Sealed container 103 Body 104 Gap 105 Volumetric pump 106 Centrifugal pump

Claims (3)

In the scroll compressor that forms a compression chamber with the orbiting scroll and the fixed scroll, and compresses the refrigerant by changing the volume of the compression chamber by rotation of the drive shaft,
The oil used to lubricate the main bearing after being supplied to the orbiting back chamber formed by the rear surface of the orbiting scroll and the end surface of the drive shaft is used to lubricate the sub bearing, and then to the oil reservoir. A scroll compressor having a return path. In a sealed container,
A compression mechanism in which a compression chamber is formed by combining a fixed scroll and a turning scroll;
An electric motor that drives the compression mechanism;
A drive shaft connecting a crank part to the orbiting scroll;
A main bearing that supports the drive shaft;
A secondary bearing for supporting the drive shaft;
An oil absorption mechanism disposed at the end of the drive shaft on the auxiliary bearing side,
In a scroll compressor, the lubricating oil is supplied to the main bearing through an oil absorption hole provided in the drive shaft, and the lubricating oil is supplied to the auxiliary bearing through the first drain oil pipe.
A scroll compressor characterized in that a second drainage pipe for guiding oil from the first drainage pipe to the auxiliary bearing is connected to the first drainage pipe. In claim 2,
A scroll compressor characterized in that the second oil drainage pipe is provided with an oil drainage section that guides the oil sump.