JP2012052527A - Scroll type fluid machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scroll type fluid machine that can easily reduce a mechanical loss of the drive energy of a scroll unit.SOLUTION: The scroll type fluid machine includes the scroll type unit (12), a frame (14), and a support mechanism (11) which supports a movable scroll (10) so as to be movable in orbit revolution in the center of a base face (10b) of the movable scroll. The support mechanism is composed of: recesses (50, 94) which are formed at either a bottom (14c) at the center side rather than a pedestal (14b) of the frame or the back face (10c) of the movable scroll; a bush (72) which is inserted into the bushes so as to be slidable; fixed shafts (16, 16a, 16b and 72e) which are protruded from the other side of either of the bottom of the frame or the back face of the movable scroll; and engagement parts (72a, 16c) at which the fixed shafts are slidably engaged with the eccentric position of the bush.

Description

  The present invention relates to a scroll type fluid machine, and more particularly to a scroll type fluid machine suitable for use as a compressor-integrated expander having a single plate type scroll.

  This type of scroll type fluid machine includes an orbiting scroll (movable scroll) end plate (substrate) provided on one side (base surface) of an orbiting scroll wrap (lap) and a fixed scroll wrap (lap) that meshes with the orbiting scroll wrap. There is known a scroll unit that includes a scroll unit, and an operation area of the scroll unit is divided into a compression operation area and an expansion operation area by a partition wall to form a compression part and an expansion part (for example, a patent) Reference 1).

Japanese Patent No. 4026747

By the way, in the above prior art, in order to give the orbiting revolving motion to the movable scroll, a cylindrical boss protrudes on the back surface, which is the surface opposite to the base surface of the movable scroll, and the eccentricity of the drive shaft is provided on this boss. Pins are connected. The drive shaft is supported on the main frame via a bearing and is driven to rotate by a drive source such as an electric motor.
In addition, a back pressure chamber is formed on the back side of the movable scroll between the main frame and the pressure of the lubricating oil, and the movable scroll is supported by the main frame via the back pressure chamber so as to be capable of revolving. .

  Here, the drive shaft is integrated with an eccentric shaft body at the eccentric pin, and a slight gap is provided between the eccentric pin and the boss and between the shaft portion other than the eccentric pin of the drive shaft and the main frame. And a bearing is provided. Since the eccentric pin and the shaft portion of the drive shaft are separated from each other in the axial direction of the drive shaft, the distance in the axial direction between the point of application of the radial load acting on the drive shaft and the fulcrum as the movable scroll revolves orbits. Combined with the presence of the above gaps, a moment of force, that is, a rollover moment of the movable scroll, acts in a direction in which the drive shaft is inclined with respect to the drive shaft, and the drive shaft hits the boss and the main frame. It becomes easy.

  Such a contact increases the mechanical loss of driving energy obtained in the scroll unit. Specifically, when the suction pressure of the working fluid to the expansion part becomes high depending on the operating state of the fluid machine, the rotational torque of the movable scroll increases, and consequently the recovery power by the fluid machine increases, and the movable scroll is moved to the outer periphery thereof. The pushing force pushing to the side and the radial load acting on the drive shaft increase. As a result, the frictional resistance of the drive shaft with respect to the movable scroll and the main frame increases, and the mechanical loss of the drive energy increases.

  On the other hand, by controlling the pressure in the back pressure chamber to be relatively high, or by adjusting the thickness of the shim interposed in the gap between the shells constituting the housing when the fluid machine is assembled, it is possible to move the fixed pressure scroll. It is conceivable to appropriately manage the gap in the axial direction of the scroll to reduce the mechanical loss of the driving energy. However, this complicates the configuration of the fluid machine, and there is a problem that it takes a long time to assemble the fluid machine.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a scroll type fluid machine that can easily reduce the mechanical loss of the drive energy of the scroll unit.

  In order to achieve the above object, the scroll type fluid machine according to claim 1 is composed of a fixed scroll and a movable scroll each having a spiral lap formed on each base surface of each substrate so as to face each other. A scroll unit that revolves around the movable scroll to form a working fluid working chamber between the wraps of the fixed and movable scrolls, and the movable scroll revolves on the outer periphery of the back surface opposite to the base surface. A frame having a pedestal portion that supports the pivoting movement and a support mechanism that supports the movable scroll so as to be able to make a revolving swivel movement at the center of the back of the movable scroll. Or a recess provided on one of the backs of the movable scroll, a bush fitted to the recess so as to be slidable, and a bottom surface of the frame or the movable scroll. A stationary shaft projecting from the other one side of the back of the Le, the fixed shaft is characterized by comprising a sliding rotatably engaged with the engaging portion at an eccentric position of the bush.

The invention according to claim 2 is characterized in that, in claim 1, in the support mechanism, the concave portion and the engaging portion are arranged so as to overlap each other in the axial direction of the fixed shaft.
Further, the invention according to claim 3 is characterized in that, in claim 1 or 2, the bush is a sliding bearing that receives relative rotation of the movable scroll and the fixed shaft.
Furthermore, in the invention according to claim 4, in any one of claims 1 to 3, the fixed shaft or the bush can be moved back and forth with respect to the frame to adjust the clearance between the base surface of the fixed scroll and the base surface of the movable scroll. It is characterized by providing a gap adjusting means.

The invention according to claim 5 is characterized in that, in claim 4, the gap adjusting means is a screw mechanism that adjusts the gap by adjusting the amount of screwing of the fixed shaft or the bush with respect to the frame.
Further, the invention according to claim 6 is characterized in that, in any one of claims 1 to 5, a reduced thickness portion is formed in the bush.

  Furthermore, in the invention described in claim 7, in any one of claims 1 to 6, the bush is provided with a balance weight.

  According to the scroll type fluid machine of the first aspect of the present invention, the movable scroll is supported so as to be capable of revolving at the center of the rear surface thereof, and the bottom surface of the center side of the pedestal portion of the frame or the movable scroll is supported. A recessed portion provided on any one of the back surfaces, a bush fitted to the recessed portion so as to be slidable, a fixed shaft projecting from either the bottom surface of the frame or the back surface of the movable scroll, and a fixed shaft A support mechanism is provided that includes an engaging portion that is slidably engaged with an eccentric position of the bush.

  With such a support mechanism, the inclination of the fixed shaft that occurs with the orbiting orbiting movement of the movable scroll can be regulated by the concave portion or the engaging portion, so that the movable shaft is movable as compared with the case where the fixed shaft is supported only by the frame. Since the rollover of the scroll can be suppressed and the frictional resistance of the movable scroll generated with respect to the frame can be reduced, the mechanical loss of the driving energy of the scroll type fluid machine can be greatly reduced.

  According to the second aspect of the present invention, in the support mechanism, the concave portion and the engaging portion are arranged so as to overlap each other in the axial direction of the fixed shaft. As a result, the radial load acting point and fulcrum acting on the fixed shaft can be juxtaposed in the radial direction of the fixed shaft, so that the moment of force generated in the direction of tilting the fixed shaft, that is, the rollover moment of the movable scroll can be reduced. It can be surely suppressed. Therefore, since the frictional resistance of the movable scroll generated with respect to the frame can be reliably reduced, the mechanical loss of the driving energy of the scroll type fluid machine can be surely reduced.

  According to a third aspect of the present invention, the bush is a sliding bearing that receives the relative rotation of the movable scroll and the fixed shaft. As a result, the thrust load and the radial load acting on the bush in accordance with the orbiting revolving motion of the movable scroll can be collectively received by the bush. Therefore, compared to the case where the thrust bearing and the radial bearing are provided separately. Further, the scroll unit can be further reduced in weight and diameter, and a large back pressure chamber, which is the space on the back side of the movable scroll, can be secured. Accordingly, since the back pressure of the movable scroll can be reduced, the frictional resistance of the movable scroll with respect to the fixed scroll can be further reduced, and the mechanical loss of the driving energy of the scroll type fluid machine can be further reduced. .

  Furthermore, according to the fourth aspect of the invention, there is provided the gap adjusting means for adjusting the gap between the base surface of the fixed scroll and the base surface of the movable scroll by allowing the fixed shaft or the bush to advance and retreat with respect to the frame. Thereby, the screwing amount of the fixed shaft with respect to the frame can be adjusted based on the dimensional error in the axial direction of the movable scroll with respect to the fixed scroll. Accordingly, since the dimensional error in the axial direction of the movable scroll with respect to the fixed scroll can be appropriately managed with a simple configuration, the frictional resistance of the movable scroll with respect to the fixed scroll can be easily reduced, and the scroll type fluid machine can be driven. The mechanical loss of energy can be further reduced.

According to the fifth aspect of the present invention, the gap adjusting means is a screw mechanism that adjusts the gap by adjusting the amount of screwing of the fixed shaft or the bush with respect to the frame. This is preferable because the clearance between the base surface of the fixed scroll and the base surface of the movable scroll can be adjusted with a simple configuration in which a screw mechanism is provided between the frame and the fixed shaft or bush.
Furthermore, according to the invention described in claim 6, by forming the thinned portion on the bush, the centrifugal force acting on the concave portion from the bush during sliding sliding of the bush is adjusted by the size and position of the thinned portion. Therefore, the sliding rotation in the recess of the bush can be easily made smooth, and the mechanical loss of the driving energy of the scroll type fluid machine can be further reduced.

  Furthermore, according to the seventh aspect of the present invention, the balance weight is provided on the bush, so that the centrifugal force acting on the recess from the bush when the bush is slid is adjusted by the weight, size and position of the balance weight. Therefore, the sliding rotation in the recess of the bush can be easily made smooth, and the mechanical loss of the driving energy of the scroll type fluid machine can be further reduced.

1 is a longitudinal sectional view of a scroll type fluid machine according to a first embodiment of the present invention. It is the top view which looked at the fixed scroll of FIG. 1 from the base surface side. It is the top view which looked at the movable scroll of FIG. 1 from the base surface side. It is sectional drawing to which the support mechanism of the movable scroll of FIG. 1 was expanded. It is a perspective view of the fixed axis | shaft of FIG. It is a perspective view of the bush of FIG. It is the top view which looked at the state which attached the bush to the fixed axis | shaft of FIG. 4 from the axial part side. It is the block diagram which showed the outline of the support mechanism of FIG. (A) When the seal ring is arranged on the fixed shaft side (center side of the movable scroll) of the rotation prevention mechanism, (b) When the seal ring is arranged on the anti-fixed shaft side (outer side of the movable scroll) of the rotation prevention mechanism It is the conceptual diagram showing the back pressure distribution of this movable scroll, and the pressing force distribution of the movable scroll with respect to a fixed scroll. It is sectional drawing to which the support mechanism which concerns on the modification of this invention was expanded. It is the block diagram which showed the outline of the support mechanism which concerns on another modification of this invention. It is the block diagram which showed the outline of the support mechanism which concerns on another modification of this invention. It is the block diagram which showed the outline of the support mechanism which concerns on another modification of this invention. It is the block diagram which showed the outline of the support mechanism which concerns on another modification of this invention. It is the block diagram which showed the outline of the support mechanism which concerns on another modification of this invention. It is a perspective view of the bush concerning another modification of the present invention. It is a perspective view of the bush concerning another modification of the present invention. It is a perspective view of the bush concerning another modification of the present invention. It is a perspective view of the bush concerning another modification of the present invention.

  FIG. 1 is a longitudinal sectional view of a scroll type fluid machine 1. The fluid machine 1 is, for example, a vertically installed compressor-integrated expander, and is inserted into a refrigeration cycle (not shown) such as a heat pump in which a supercritical carbon dioxide refrigerant circulates. The refrigeration cycle is an air conditioner (not shown). The fluid machine 1 includes a later-described expansion unit 2 that performs an expansion operation by the pressure of the refrigerant, and a later-described compression unit 4 that performs a compression operation by the expansion operation of the expansion unit 2. I have.

  The fluid machine 1 includes a housing 6, in which a scroll unit 12 mainly composed of a fixed scroll 8 and a movable scroll 10 that revolves with respect to the fixed scroll 8 and a revolving swivel of the movable scroll 10. A main frame (frame) 14 and a fixed shaft 16 that are movably supported, and a support member 18 that supports the fixed shaft 16 together with the main frame 14 are disposed.

  The housing 6 includes an outer peripheral portion 14 a of the main frame 14, a cap-shaped top shell 20 that covers the upper portion of the main frame 14, and a cap-shaped bottom shell 22 that covers the lower portion of the main frame 14. The housing 6 is sealed by fastening the shells 20 and 22 with bolts 25 so as to sandwich the outer peripheral portion 14a through the O-ring 23. A pressure obtained by compressing the refrigerant taken in from the refrigeration cycle as the working fluid of the fluid machine 1 by the compression unit 4 acts in the sealed housing 6.

  Specifically, the top shell 20 includes an expansion side suction pipe 24 that sucks the refrigerant taken in from the refrigeration cycle into the expansion section 2, and an expansion side discharge pipe that discharges the refrigerant expanded in the expansion section 2 toward the refrigeration cycle. 26 and a compression side discharge pipe 28 that discharges the refrigerant compressed by the compression unit 4 toward the refrigeration cycle. The expansion side suction pipe 24 and the expansion side discharge pipe 26 are respectively opened to an expansion side suction chamber 30 and an expansion side discharge chamber 32 formed in the substrate 8 a of the fixed scroll 8, and the compression side discharge pipe 28 is the top. The compression side discharge chamber 34 formed inside the shell 20 is opened.

  The outer peripheral portion 14a of the main frame 14 is connected to a compression side suction pipe 36 for sucking refrigerant taken from the refrigeration cycle into the compression section 4, and the compression side suction pipe 36 and the expansion side discharge pipe 26 are fixed scrolls. 8 are opened in the compression side suction chamber 38 and the expansion side discharge chamber 32 formed in the eight substrates 8a.

On the other hand, a lubricating oil chamber 40 is formed inside the bottom shell 22, and lubricating oil for lubricating the scroll unit 12 is stored in the lubricating oil chamber 40.
The compression-side suction chamber 38 is provided with an oil feed hole 62 (see FIG. 2), which will be described later, penetrating the substrate 8 a of the fixed scroll 8 and the main frame 14, and the lubricating oil in the lubricant chamber 40 through the oil feed hole 62. Is sent to the compression side suction chamber 38.

An oil supply passage 42 is bored in the fixed shaft 16 along the axial direction of the fixed shaft 16. The oil supply passage 42 has a lubricating oil chamber 40 and a boss (concave portion) 50 described later on the upper end side of the fixed shaft 16. It is open to the inner space.
The fixed scroll 8 is fixed to the inner side of the outer peripheral portion 14a of the main frame 14, and a compression side discharge hole 44, which will be described later, is slightly in the radial direction of the fixed scroll 8 with respect to the compression side suction chamber 38 of the substrate 8a of the fixed scroll 8. Is formed through. An oil separator 45 that separates the lubricating oil in the refrigerant is attached to the opening of the compression side discharge hole 44 with respect to the compression side discharge chamber 34.

  The movable scroll 10 is supported on the pedestal portion 14b of the main frame 14 through a rotation prevention mechanism 46 such as an Oldham ring so as to be capable of revolving without rotating, and an annular seal ring 48 is provided on the outer peripheral side of the rotation prevention mechanism 46. Is provided. The rotation prevention mechanism 46 and the seal ring 48 are inserted into the pedestal portion 14b, and are slidably contacted with the back surface 10c, which is the surface opposite to the base surface 10b of the substrate 10a, along with the revolving turning motion of the movable scroll 10. Further, a cylindrical boss 50 into which a bush 72 (described later) is inserted so as to be slidably rotatable is projected from the back surface 10c of the movable scroll 10.

  Here, the scroll unit 12 of the present embodiment can form both the compression unit 4 and the expansion unit 2 as a refrigerant working chamber by a set of the fixed scroll 8 and the movable scroll 10 in the compressor-integrated expander. This is a so-called single-plate scroll unit, and the fixed shaft 16 only supports the movable scroll 10 together with the main frame 14 so as to be capable of revolving, and the fixed shaft 16 itself is not driven to rotate.

  Specifically, as shown in FIG. 2, an annular intermediate partition wall (annular wall) 52 and an annular outer partition wall 54 are erected on the base surface 8 b of the fixed scroll 8. A spiral outer fixed scroll wrap (wrap) 56 is provided between the outer partition wall 54 and a spiral inner fixed scroll wrap (wrap) 58 on the center side of the intermediate partition wall 52. Further, an annular groove 61 into which the seal ring 59 (see FIG. 1) is fitted is recessed in the end surface of the intermediate partition wall 52 on the base surface 8b.

  On the substrate 8 a of the fixed scroll 8, a compression side suction chamber 38 is formed at the outer peripheral end of the compression portion 4 slightly inside the outer partition wall 54, and compressed to the inner peripheral end of the compression portion 4 slightly outside the intermediate partition wall 52. A side discharge hole 44 is formed. Further, the expansion side discharge chamber 32 is formed at the outer peripheral end of the expansion portion 2 slightly inside the intermediate partition wall 52 and the expansion side suction chamber 30 is formed at the central portion that is the inner peripheral end of the expansion portion 2 on the substrate 8a. Has been. Further, an annular oil groove 60 is formed on the substrate 8a slightly outside the outer partition wall 54, and is countersunk at a predetermined depth with a diameter larger than the groove width provided on the oil groove 60. The oil feed hole 62 described above is formed on the bottom surface of the formed recess.

On the other hand, as shown in FIG. 3, on the base surface 10 b of the movable scroll 10, a spiral outer movable scroll wrap (wrap) 64 that meshes with the outer fixed scroll wrap 56 and a spiral that meshes with the inner fixed scroll wrap 58. The inner movable scroll wrap (wrap) 66 is erected in the direction of the opposite spiral.
According to the scroll unit 12 described above, the expansion portion 2 is formed inside the intermediate partition wall 52, and the compression portion 4 is formed between the intermediate partition wall 52 and the outer partition wall 54.

  Specifically, as indicated by a solid arrow in FIG. 1, the refrigerant sucked from the expansion side suction pipe 24 is taken into the expansion unit 2 through the expansion side suction chamber 30, and the scrolls 8, 10 cooperate with each other. By working, it is expanded in an expansion chamber formed between the laps 58 and 66. The volume of the expansion chamber is increased while moving toward the outer peripheral side of each of the scrolls 8 and 10, and accordingly, the movable scroll 10 is revolved around the axis of the fixed scroll 8.

The refrigerant used for the revolving orbiting motion of the movable scroll 10 is discharged toward the refrigeration cycle outside the housing 6 through the expansion-side discharge chamber 32 through the expansion-side discharge chamber 32.
On the other hand, the refrigerant sucked from the compression side suction pipe 36 is taken into the compression unit 4 through the compression side suction chamber 38, and the movable scroll 10 revolves around the axis of the fixed scroll 8 along with the formation of the expansion chamber described above. By moving, the scrolls 8 and 10 are compressed in a compression chamber formed between the wraps 56 and 64 by cooperating with each other. The volume of the compression chamber is reduced while moving toward the center of each of the scrolls 8 and 10 as the orbiting scroll 10 revolves. Then, the refrigerant that has been increased in pressure as the volume of the compression chamber is reduced is discharged toward the refrigeration cycle outside the housing 6 via the compression side discharge hole 44 and the compression side discharge chamber 34 via the compression side discharge pipe 28.

  Further, in this process, as indicated by a dotted arrow in FIG. 1, the refrigerant discharged from the compression side discharge hole 44 to the compression side discharge chamber 34 passes through the oil separator 45 and the lubricating oil in the refrigerant is contained in the refrigerant. Are separated. The lubricating oil separated from the refrigerant is stored in the lubricating oil chamber 40 through an oil return path 63 formed between the notch 47 formed on the outer peripheral surface of the fixed scroll substrate and the inner peripheral surface of the main frame 14. The The lubricating oil stored in the lubricating oil chamber 40 rises in the oil supply passage 42 due to its high pressure and is discharged from the upper end of the fixed shaft 16, and will be described later as a needle bearing 70, a tapered roller bearing 78, and a bearing 80 (all refer to FIG. 4). ) To the back pressure chamber 68 formed between the base portion 14b of the main frame 14 and the back surface 10c of the movable scroll 10.

In the back pressure chamber 68, the sliding portion between the rotation prevention mechanism 46, the base portion 14b, and the back surface 10c of the movable scroll 10 is lubricated by the lubricating oil, and the movable scroll 10 is fixed by the pressure of the lubricating oil as will be described later. The scroll 8 is pressed and urged, and thereby, the smooth revolving motion of the movable scroll 10 with respect to the fixed scroll 8 becomes possible.
Thus, in the fluid machine 1, the scroll unit 12 is driven by the expansion energy of the refrigerant, and the compression energy of the refrigerant is generated by the driving force of the scroll unit 12. At this time, as described above, the fixed shaft 16 and the main frame 14 constitute the support mechanism 11 that supports the movable scroll 10 so as to be capable of revolving.

Specifically, as shown in the enlarged sectional view of the support mechanism 11 of the movable scroll 10 in FIG. 4, a shaft portion (fixed shaft) 16 a is formed at the upper end of the fixed shaft 16, and the shaft portion 16 a has a needle bearing 70. And is inserted into a hole (engagement portion) 72 a of the bush 72.
On the other hand, a base (fixed shaft) 16b whose diameter is expanded from the shaft portion 16a is formed at the lower end of the fixed shaft 16, and the fixed shaft 16 is fixed to the main frame 14 and the support member 18 at the base portion 16b.

More specifically, a threaded portion 74 is formed on the outer peripheral surface of the base portion 16 b, and a bottom hole 14 d that penetrates the threaded portion 74 through the bottom surface 14 c of the main frame 14 and a support member 18 disposed on the lower end surface of the main frame 14. The fixed shaft 16 is fastened to the main frame 16 by screwing with the penetrating through hole 18a (screw mechanism, gap adjusting means).
Also, a jig hole 76 is provided in the lower end surface of the base portion 16b, and a fixed shaft 16 for the main frame 14 is attached to the main frame 14 at the stage of assembling the scroll unit 12 by fitting and operating a jig (not shown) in the jig hole 76. The gap between the base surfaces 8b and 10b can be adjusted by adjusting the amount of screwing.

On the other hand, the bush 72 is inserted into the boss 50 through a tapered roller bearing 78 so as to be slidable. The tapered roller bearing 78 collectively receives a thrust load and a radial load acting on the bush 72 as the movable scroll 10 revolves.
Further, a flange 72b having a diameter larger than the diameter of the boss 50 is formed at the lower end of the bush 72, and a bearing 80 is disposed between the flange 72b and the base portion 16b. Further, a balance weight 82 having an L shape in cross section is formed integrally with the collar portion 72b, and the balance weight 82 rotates in accordance with the revolving orbiting motion of the movable scroll 10 in the space 84 between the movable scroll 10 and the main frame 14. Is done.

As described above, the fixed shaft 16 supports the movable scroll 10 through the needle bearing 70, the bush 72, the tapered roller bearing 78, and the bearing 80 so as to be capable of revolving. The support mechanism 11 includes the boss 50, the bush 72, and the The hole portion 72a, the shaft portion 16a of the fixed shaft 16, and the base portion 16b are configured.
Here, as shown in the perspective view of the fixed shaft 16 in FIG. 5, the shaft portion 16 a is formed so as to be concentric with the axial center 86 of the entire fixed shaft 16 and is not eccentric.

  On the other hand, as shown in the perspective view of the bush 72 in FIG. 6, the hole 72 a is provided at a position eccentric with respect to the shaft center 88 of the entire bush 72. In other words, as shown in detail in the top view of the state in which the bush 72 is assembled to the fixed shaft 16 in FIG. 7 as viewed from the shaft portion 16 a side, the bush 72 has a smooth revolving motion of the movable scroll 10 relative to the fixed scroll 8. The fixed shaft 16 and the shaft portion 86a of the shaft portion 16a are assembled eccentrically with a predetermined eccentricity.

Further, as shown in the schematic configuration diagram of the support mechanism 11 in FIG. 8, in the support mechanism 11, the boss 50 and the hole 72a are arranged to overlap each other in the axial direction of the shaft portion 16a.
Specifically, the inner peripheral surface 72c of the hole portion 72a in which the shaft portion 16a is slidably contacted in the axial direction via the needle bearing 70 with the revolution turning motion of the movable scroll 10, and the bush with the revolution turning motion of the movable scroll 10. The inner peripheral surface 50a of the boss 50 in which 72 is slidably contacted in the axial direction via the tapered roller bearing 78 is positioned so that at least a part thereof overlaps in the axial direction of the shaft portion 16a. The hole 72a is not limited to a through hole, and may be a bottomed hole.

As described above, in this embodiment, instead of the eccentric shaft in which the eccentric pin is integrated, the eccentric shaft is fixed to the true fixed shaft 16 and to the position eccentric with respect to the axis of the fixed shaft 16. The movable scroll 10 is supported by the support mechanism 11 so as to be capable of revolving orbiting.
By such a support mechanism 11, the inclination of the shaft portion 16 a generated by the revolving turning motion of the movable scroll 10 can be restricted by the hole 72 a, so that the shaft portion 16 a is supported only by the frame 14. In particular, when the hole 72a has a bottomed hole as shown in FIG. 8, the rollover of the movable scroll 10 can be effectively suppressed, and the friction of the movable scroll 10 generated with respect to the frame 14 can be suppressed. Since the resistance can be reduced, the mechanical loss of the driving energy of the fluid machine 1 can be greatly reduced.

  Further, in the support mechanism 11, the boss 50 and the hole 72a are arranged to overlap each other in the axial direction of the shaft portion 16a. As a result, since the point of application and the fulcrum of the radial load acting on the shaft portion 16a can be juxtaposed in the radial direction of the shaft portion 16a, the moment of force generated in the direction in which the shaft portion 16a is tilted, that is, the movable scroll 10 The overturning moment can be suppressed. Therefore, the overturning of the movable scroll 10 can be reliably suppressed, and the frictional resistance of the movable scroll 10 generated with respect to the frame 14 can be reliably reduced, so that the mechanical loss of the driving energy of the fluid machine 1 is ensured. Can be reduced.

  Further, by forming the screw portion 74 and the jig hole 76 in the base portion 16b of the fixed shaft 16, the main frame is based on the dimensional error in the axial direction of the movable scroll 10 with respect to the fixed scroll 8 at the stage of assembling the scroll unit 12. The amount of screwing of the fixed shaft 16 with respect to 14 can be adjusted. Accordingly, since the dimensional error in the axial direction of the movable scroll 10 with respect to the fixed scroll 8 can be appropriately managed with a simple configuration, the frictional resistance of the movable scroll 10 with respect to the fixed scroll 8 can be easily reduced. The mechanical loss of the driving energy of 1 can be further reduced.

  Further, since the balance weight 82 is provided on the bush 72, the centrifugal force acting on the boss 50 from the bush 72 when the bush 72 is slidably rotated can be adjusted by the weight, size, and position of the balance weight 82. The sliding rotation of the boss 50 of the bush 72 can be easily made smooth, and the mechanical loss of the driving energy of the fluid machine 1 can be further reduced.

  Further, in the back pressure chamber 68, the seal ring 48 is arranged on the outer peripheral side of the movable scroll 10 with respect to the rotation prevention mechanism 46, so that the seal ring 48 is arranged on the center side of the movable scroll 10 with respect to the rotation prevention mechanism 46. Compared to the case, the pressurizing range in the back pressure chamber 68 can be increased, and the necessary pressing force on the movable scroll 10 can be obtained with a low back pressure.

  Specifically, FIG. 9A shows the distribution of the back pressure Pb of the movable scroll 10 when the seal ring 48 is arranged on the fixed shaft 16 side (the center side of the movable scroll 10) of the rotation prevention mechanism 46, and the fixed scroll 8. The distribution of the pressing force Fp of the movable scroll 10 with respect to is shown. In this case, since the area of the back pressure chamber 68 on the fixed ring 16 side of the seal ring 48, that is, the inner pressure receiving region 68a, which is the inner region of the seal ring 48, is reduced, the entire movable scroll 10 is moved by the pressing force Fp. In order to push up, it is necessary to apply a high pressure to the inner pressure receiving region 68 a and to increase the pressure of the outer pressure receiving region 68 b on the side opposite to the fixed shaft 16 of the seal ring 48, that is, the region outside the seal ring 48.

  On the other hand, in this embodiment, the seal ring 48 is disposed on the anti-fixed shaft side (the outer peripheral side of the movable scroll 10) of the rotation prevention mechanism 46. FIG. 9B shows the back pressure of the movable scroll 10 at this time. The distribution and the pressing force distribution of the movable scroll 10 with respect to the fixed scroll 8 are shown. In this case, the area of the inner pressure receiving region 68a is increased, and a large pressing force Fp similar to that in FIG. 9A can be obtained with a lower back pressure Pb than in the case of FIG. 9A. . Therefore, since the pressing surface pressure of the movable scroll 10 against the fixed scroll 8 can be reduced with a simple configuration that only changes the position of the seal ring 48, the performance of the scroll unit 12 can be further simplified and improved. This is preferable.

  In addition, a complicated lubricating oil circuit is formed such that the lubricating oil pressure is increased in order to appropriately manage the back pressure for preventing the separation of the movable scroll 10 in the axial direction relative to the fixed scroll 8, so that the inner peripheral side of the seal ring 48 is formed. There is no need to increase the pressure in the back pressure chamber 68. Therefore, the oil supply means for the scroll unit 12 can be simplified, which is preferable because the performance of the scroll unit 12 can be further simplified and improved.

Although the description of the embodiment of the present invention has been completed above, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, the tapered roller bearing 78 is interposed between the boss 50 and the bush 72. However, the present invention is not limited to this, and the support mechanism according to the modification of the present invention in FIG. As shown in the enlarged sectional view, a thrust bearing 90 is provided between the inner peripheral surface 50b of the boss 50 and the outer peripheral surface 72d of the bush 72, and a radial bearing 92 is provided between the end surface 50c of the boss 50 and the flange portion 72b. May be provided. However, in the case where the tapered roller bearing 78 is provided, the thrust load and the radial load acting on the bush 72 accompanying the revolution turning motion of the movable scroll 10 can be collectively received by the tapered roller bearing 78. As compared with the case where the radial bearings 90 and 92 are separately provided, the configuration of the fluid machine 1 is simplified and is preferable.

  Further, as in the above-described embodiments and modifications, the bush 72 itself is a sliding bearing that receives the relative rotation of the movable scroll 10 and the shaft portion 16a without providing the tapered roller bearing 78 and the bearings 70, 90, and 92. Also good. In this case, the thrust load and the radial load acting on the bush 72 as the orbiting scroll 10 revolves can be collectively received by the bush.

  Moreover, the scroll unit 12 can be further reduced in weight and diameter as compared with the case where the tapered roller bearing 78 and the bearings 70, 90, and 92 are provided, and the back pressure chamber 68 can be secured large. Accordingly, since the back pressure of the movable scroll 10 can be reduced, the frictional resistance of the movable scroll 10 with respect to the fixed scroll 8 can be further reduced, and the mechanical loss of the driving energy of the fluid machine 1 can be further reduced. Can do.

Furthermore, in the above embodiment, a screw mechanism including the screw portion 74 and the jig hole 76 is used as a gap adjusting means between the base surfaces. However, the base portion 16b can be moved forward and backward with respect to the main frame 16. The present invention is not limited to this as long as the gap between the base surfaces 8b and 10b can be adjusted.
Furthermore, in the above embodiment, the support mechanism 11 includes the boss 50, the bush 72, the base portion 16b, the shaft portion 16a, and the hole portion 72a. However, the present invention is not limited to this, and as shown in FIG. Alternatively, a recess 94 may be provided on the bottom surface 14 c of the frame 14, and the bush 72 may be slidably inserted into the recess 94, and the base 16 b may protrude from the back surface 10 c of the movable scroll 10.

Further, as shown in FIG. 12 as a modification of FIG. 8 and as shown in FIG. 13 as a modification of FIG. 11, the fixed shaft 16 may be formed only by the shaft portion 16a without the base portion 16b. In this case, since the axial direction of the fixed shaft 16 can be further shortened, the scroll unit 12 can be further reduced in weight and size, which is preferable.
Further, as shown in FIG. 14, a bush 72 is slidably fitted into the boss 50, the base portion 16b is projected from the bottom surface 14c of the frame 14, and is fixed only by the base portion 16b without the shaft portion 16a. A shaft 16 is formed, a hole (engaging portion) 16c is provided in the base 16b instead of the hole 72a, and a shaft (fixed shaft) 72e is embedded in the bush 72 instead of the shaft 16a. The shaft portion 72e may be fitted into the hole portion 16c so as to be slidable by fitting the outer peripheral portion of 16b into the bush 72 inward.

  Further, as shown in FIG. 15, the bush 72 is slidably fitted into the recess 94, the base portion 16b is protruded from the rear surface 10c of the movable scroll 10, and the shaft portion 16a is not provided but only the base portion 16b. As in the case of FIG. 14, the fixed shaft 16 is formed, the hole portion 16 c is provided in the base portion 16 b, the shaft portion 72 e is embedded in the bush 72, and the outer peripheral portion of the base portion 16 b is fitted inside the bush 72. By inserting the shaft portion 72e, the shaft portion 72e may be fitted in the hole portion 16c so as to be slidable. 14 and 15, the axial direction of the fixed shaft 16 can be further shortened, which is preferable because the scroll unit 12 can be further reduced in weight and size.

11 to 15, the rollover of the movable scroll 10 can be suppressed compared to the case where the shaft portion 16 a is supported only by the frame 14, and the movable scroll 10 generated with respect to the frame 14 can be suppressed. Since the frictional resistance can be reduced, the mechanical loss of the driving energy of the fluid machine 1 can be greatly reduced.
Further, as shown in FIGS. 16 to 19, instead of the balance weight 82 or in combination with the balance weight 82, a part of the collar portion 72 is notched into a flat shape, or the bush 72 is moved in the axial direction. Alternatively, there may be provided a thinned portion 96 formed by penetrating or denting in the radial direction.

In this case, since the centrifugal force acting on the boss 50 from the bush 72 when the bush 72 is slidably rotated can be adjusted by the size and position of the thinning portion 96, the slidable rotation of the bush 72 on the boss 50 is easy. Therefore, the mechanical loss of the driving energy of the fluid machine 1 can be further reduced.
In particular, when the balance weight 82 is not required or can be downsized by adjusting the size and position of the thinned portion 96, the scroll unit 12 can be further reduced in weight and downsized. A large capacity of the chamber 68 can be secured. Accordingly, since the back pressure of the movable scroll 10 can be reduced, the frictional resistance of the movable scroll 10 with respect to the fixed scroll 8 can be further reduced, and the mechanical loss of the driving energy of the fluid machine 1 can be further reduced. Is preferable.

  Finally, in the above embodiment, the case where the present invention is applied to the compressor-integrated expander having the single-plate scroll unit 12 is described. However, the present invention is not limited to this, and the present invention is not limited to a single scroll. The present invention can be applied to any fluid machine including a scroll unit such as an expander or a compressor having a unit.

1 Scroll-type fluid machine 8 Fixed scroll 8a Fixed scroll substrate (substrate)
8b Base surface (base surface) of fixed scroll substrate
10. Movable scroll 10a Movable scroll substrate (substrate)
10b Base surface (base surface) of movable scroll substrate
10c Back side of movable scroll board (back side)
11 Support Mechanism 12 Scroll Unit 14 Main Frame (Frame)
14a Outer peripheral part 14b Pedestal part 14c Bottom face 16 Fixed shaft 16a Shaft (fixed shaft)
16b Base (fixed shaft)
16c hole (engagement part)
50 Boss (concave)
56 Outer fixed scroll wrap (wrap)
58 Inside fixed scroll wrap (wrap)
64 Outside movable scroll wrap (wrap)
66 Inside movable scroll wrap (wrap)
72 Bush 72a Hole (engagement part)
72e Shaft (fixed shaft)
82 Balance weight 94 Concave part 96 Thinning part

Claims (7)

Each of the bases of each substrate is composed of fixed and movable scrolls each having a spiral wrap opposed to each other, and the movable scroll is revolved around the axis of the fixed scrolls to rotate the fixed and movable scrolls. A scroll unit forming a working fluid working chamber between the laps;
A frame having a pedestal that supports the orbiting scroll so as to be capable of revolving orbiting at the outer periphery of the back surface opposite to the base surface;
A support mechanism that supports the orbiting scroll so as to be capable of revolving at the center of the back surface;
The support mechanism is
A concave portion provided on either the bottom surface of the frame on the center side of the pedestal portion or the back surface of the movable scroll;
A bush fitted into the recess so as to be slidable,
A fixed shaft protruding from the other side of the bottom surface of the frame or the back surface of the movable scroll;
The scroll fluid machine according to claim 1, wherein the fixed shaft includes an engaging portion that is slidably engaged with an eccentric position of the bush.   2. The scroll type fluid machine according to claim 1, wherein in the support mechanism, the concave portion and the engagement portion are arranged to overlap each other in an axial direction of the fixed shaft.   The scroll type fluid machine according to claim 1, wherein the bush is a sliding bearing that allows the movable scroll and the fixed shaft to rotate relative to each other.   2. A clearance adjusting means for adjusting a clearance between the base surface of the fixed scroll and the base surface of the movable scroll by allowing the fixed shaft or the bush to advance and retreat with respect to the frame. The scroll type fluid machine according to any one of 1 to 3.   The scroll type fluid machine according to claim 4, wherein the gap adjusting means is a screw mechanism that adjusts the gap by adjusting a screwing amount of the fixed shaft or the bush with respect to the frame.   The scroll type fluid machine according to any one of claims 1 to 5, wherein a thinning portion is formed in the bush.   The scroll fluid machine according to any one of claims 1 to 6, wherein a balance weight is provided on the bush.

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