Scroll fluid machine

Abstract

A scroll fluid machine according to one embodiment of the present invention comprises: a fixed scroll part; a turning scroll part; a turning jacket part including a jacket inner surface which covers a turning back surface of the turning scroll part and connected to the turning scroll part; and a drive shaft connected to the turning scroll part via the turning jacket part. A tip part of the drive shaft is inserted into the turning jacket part, and is accommodated in an internal space formed between the turning back surface and the jacket inner surface. A refrigerant supply flow path that opens to the tip part, is fluidly connected to the internal space, and supplies a refrigerant to the internal space, is formed in the drive shaft. A rotary blade part, which is provided at the tip part and rotates together with the drive shaft to feed the refrigerant to the outside of the drive shaft, is accommodated in the internal space.

Description

Scroll fluid machinery

[0001] The present invention relates to a scroll fluid machine.

[0002] A scroll fluid machine includes a pair of scrolls that are rotatable relative to each other. The scroll fluid machine compresses or expands a fluid by changing the volume of an internal space formed between the pair of scrolls. In a scroll fluid machine, temperature rise occurs due to friction between components during operation and the effects of fluid compression or expansion. Because such temperature rise can cause problems such as mechanical distortion of the scrolls, cooling techniques for suppressing temperature rise in the scrolls have been studied. For example, Patent Document 1 discloses a scroll cooling technique in which a flow path is formed in an idler shaft that aligns the scrolls, and a cooling fluid is sent to the scrolls through the flow path.

[0003] International Publication No. 2019 / 108238

[0004] In the technology of Patent Document 1, an idler shaft, which has a flow path through which a cooling fluid flows, is attached to the outer edge of the scroll. Therefore, the cooling fluid that flows into the flow path of the idler shaft flows from the outer periphery of the scroll toward the center. In this case, cooling by the cooling fluid is performed from the outer periphery of the scroll. However, since the temperature rise described above tends to be significant in the center of the scroll, it is difficult to efficiently cool the scroll using a technology in which cooling is performed from the outer periphery of the scroll. Therefore, further improvement in cooling performance is desired.

[0005] The present invention provides a scroll fluid machine capable of improving cooling performance.

[0006] A scroll fluid machine according to one embodiment of the present invention includes a fixed scroll section including a fixed main surface on which a spiral-shaped fixed wrap is formed and a fixed back surface facing the opposite side of the fixed main surface; an orbiting scroll section including an orbiting main surface on which a spiral-shaped orbiting wrap is formed and facing the fixed wrap, and an orbiting back surface facing the opposite side of the orbiting main surface; an orbiting jacket section including an inner jacket surface covering the orbiting back surface and connected to the orbiting scroll section; and a drive shaft connected to the orbiting scroll section via the orbiting jacket section and orbiting the orbiting scroll section relative to the fixed scroll section. The tip of the drive shaft is inserted into the orbiting jacket section and housed in an internal space formed between the orbiting back surface and the inner jacket surface. The drive shaft has a refrigerant supply passage that opens to the tip, fluidly connects to the internal space, and supplies refrigerant to the internal space. A rotating vane section is provided at the tip of the drive shaft and rotates together with the drive shaft to send refrigerant to the outside of the drive shaft.

[0007] In the scroll fluid machine, a drive shaft that rotates the orbiting scroll is connected to the orbiting scroll via an orbiting jacket. The tip of the drive shaft is housed in an internal space between the inner jacket surface of the orbiting jacket and the orbiting back surface of the orbiting scroll. The drive shaft has a refrigerant supply passage that opens to the tip, fluidly connects to the internal space, and supplies refrigerant to the internal space. With this configuration, the refrigerant supplied to the internal space from the refrigerant supply passage that opens to the tip of the drive shaft can actively cool the central portion of the orbiting scroll, where temperature rise is likely to be significant. This effectively prevents temperature rise in the orbiting scroll. Furthermore, in the scroll fluid machine, a rotating vane that rotates with the drive shaft and sends refrigerant to the outside of the drive shaft is housed in the internal space between the inner jacket surface and the orbiting back surface. In this case, the rotational driving force of the drive shaft can be used to form a refrigerant flow from the central portion of the orbiting scroll to the outside, thereby efficiently cooling the orbiting scroll from the central portion to the outside. Therefore, the scroll fluid machine can improve cooling performance.

[0008] In one embodiment of the scroll fluid machine, the rotating vane portion may include a rotating base portion extending from the tip end portion. The refrigerant supply passage may include a supply outlet opening at a position in the tip end portion closer to the back surface of the orbiting scroll than the rotating vane portion. By locating the supply outlet closer to the orbiting scroll portion in this manner, the cooling effect of the refrigerant supplied from the supply outlet on the central portion of the orbiting scroll portion can be enhanced.

[0009] In one embodiment of the scroll fluid machine, the supply outlet may open to a tip surface of the tip portion that faces the orbiting back surface. The refrigerant supply passage may further include a supply inlet that opens to an outer surface of the drive shaft that is positioned outside the orbiting jacket portion and that introduces refrigerant into the refrigerant supply passage. When the supply outlet of the refrigerant supply passage opens to the tip surface in this manner, the distance between the supply outlet and the orbiting scroll section is further shortened, thereby further enhancing the cooling effect on the central portion of the orbiting scroll section. Furthermore, when the supply inlet of the refrigerant supply passage opens to the outer surface of the drive shaft, the refrigerant supply passage is less likely to interfere with components around the drive shaft, unlike when the supply inlet of the refrigerant supply passage opens to an end surface of the drive shaft opposite the tip surface. As a result, the degree of freedom in the layout of components around the drive shaft can be increased.

[0010] In one embodiment of the scroll fluid machine, at least a portion of the tip end portion may be an eccentric shaft portion that is eccentric from the rotation axis of the drive shaft. The rotating vane portion may be provided on the eccentric shaft portion. In this case, a preferred embodiment can be achieved in which a refrigerant flow is formed from the center of the orbiting scroll portion to the outside by utilizing the rotational driving force of the drive shaft.

[0011] In one embodiment of the scroll fluid machine, the rotating vane portion may include a rotary base portion extending from the tip end portion, and a plurality of vanes arranged around the drive shaft so as to rise from the rotary base portion. In this case, it is easy to obtain a rotating vane portion that sends refrigerant from the center of the orbiting scroll portion to the outside.

[0012] In one embodiment of the scroll fluid machine, the orbiting jacket portion may include a bearing holder formed to surround a bearing supporting the drive shaft and hold the bearing. In this case, the orbiting jacket portion can have both the function of forming an internal space through which the refrigerant flows between the jacket inner surface and the orbiting back surface, and the function of holding the bearing supporting the drive shaft.

[0013] In one embodiment of the scroll fluid machine, the drive shaft may be formed with a refrigerant discharge passage aligned with the refrigerant supply passage. The refrigerant discharge passage may open at the tip end and be fluidly connected to the internal space, and may discharge the refrigerant supplied to the internal space. In this case, the refrigerant that has exchanged heat with the orbiting scroll portion in the internal space can be discharged to the outside through the refrigerant discharge passage that opens at the tip end of the drive shaft. This improves cooling efficiency using the refrigerant.

[0014] In one embodiment of the scroll fluid machine, the rotating blade portion may include a rotating base portion extending from the tip portion. The refrigerant supply passage may include a supply outlet that opens at a position in the tip portion closer to the rear surface of the rotating blade than the rotating blade portion. The refrigerant discharge passage may include a discharge inlet that opens at a position in the tip portion farther from the rear surface of the rotating blade than the rotating blade portion. In this case, by utilizing a flow formed in the internal space as the rotating blade portion rotates, the refrigerant can be easily guided from the supply outlet of the refrigerant supply passage to the discharge inlet of the refrigerant discharge passage. This makes it easy to achieve the effect of improving cooling efficiency using the refrigerant.

[0015] In one embodiment of the scroll fluid machine, the supply outlet may be formed in a tip surface of the tip portion facing the orbiting back surface. The discharge inlet may be formed in a tip side surface of the tip portion extending from the tip surface to the opposite side from the orbiting back surface. When the supply outlet of the refrigerant supply passage opens to the tip surface in this manner, the distance between the supply outlet and the orbiting scroll section is further shortened, thereby further enhancing the cooling effect of the refrigerant supplied from the supply outlet on the central portion of the orbiting scroll section. Furthermore, when the discharge inlet of the refrigerant discharge passage opens to the tip side surface, a flow formed in the internal space due to rotation of the rotating vane section can be utilized to easily form a refrigerant flow from the supply outlet to the discharge inlet, thereby easily achieving the effect of improving cooling efficiency using the refrigerant.

[0016] In one embodiment of the scroll fluid machine, the refrigerant discharge passage may further include a discharge outlet that opens on an outer surface of the drive shaft that is positioned outside the orbiting jacket portion and that discharges the refrigerant that has flowed into the refrigerant discharge passage. In this case, unlike when the discharge outlet of the refrigerant discharge passage opens on the end surface of the drive shaft opposite the tip surface, the refrigerant discharge passage is less likely to interfere with components around the drive shaft. As a result, the degree of freedom in layout of the components around the drive shaft can be increased.

[0017] In one embodiment of the scroll fluid machine, the inner surface of the jacket may include an opposing surface facing the orbiting back surface and an inner surface connecting the orbiting back surface and the opposing surface and surrounding the rotating vane portion. The internal space may include a first spatial region formed between the orbiting back surface and the rotating base and fluidly connected to the supply outlet, a second spatial region formed between the rotating base and the opposing surface and fluidly connected to the discharge inlet, and a third spatial region formed between the rotating base and the inner surface and connecting the first spatial region and the second spatial region. In this case, a spatial region through which the refrigerant can flow can be formed around the rotating vane portion, and the spatial region can be used to easily form a flow of refrigerant from the supply outlet to the discharge inlet.

[0018] In one embodiment of the scroll fluid machine, the inner surface may include, in a cross section including the rotation axis of the drive shaft and passing through the discharge outlet, a first inner surface portion facing the discharge outlet and a second inner surface portion located opposite the first inner surface portion. The second inner surface portion may have a step portion protruding toward the rotating vane portion. In this case, the step portion can narrow the gap between the second inner surface portion and the rotating vane portion, thereby preventing refrigerant from moving through the gap. As a result, the refrigerant supplied from the supply outlet can easily flow through the gap between the first inner surface portion and the rotating vane portion to the discharge inlet. This makes it possible to easily guide the refrigerant from the supply outlet to the discharge inlet.

[0019] In one embodiment of the scroll fluid machine, the orbiting scroll portion and the fixed scroll portion may be formed with a refrigerant discharge passage extending from the orbiting scroll portion to the fixed scroll portion. The refrigerant discharge passage may open to the back surface of the orbiting scroll portion, be fluidly connected to the internal space, and discharge the refrigerant supplied to the internal space. By forming the refrigerant discharge passage in the orbiting scroll portion and the fixed scroll portion in this manner, both the orbiting scroll portion and the fixed scroll portion can be efficiently cooled.

[0020] In one embodiment of the scroll fluid machine, a fixed inlet for taking in gas to be compressed or expanded may be formed on the fixed back surface at a position offset from the rotation axis of the drive shaft. The refrigerant discharge passage may open on the fixed back surface at a position opposite the fixed inlet across the rotation axis. In this case, it is possible to reduce the possibility of the gas taken in at the fixed inlet and the refrigerant flowing through the refrigerant discharge passage being mixed together.

[0021] In one embodiment of the scroll fluid machine, a shaft seal may be provided in the internal space adjacent to a bearing supporting the drive shaft to prevent the refrigerant from moving to the bearing. In this case, even when cooling water is used as the refrigerant, the shaft seal can prevent the cooling water from contacting the bearing, thereby avoiding bearing malfunctions caused by the cooling water contacting the bearing.

[0022] According to the present invention, a scroll fluid machine capable of improving cooling performance is provided.

[0023] Fig. 1 is a perspective view showing a scroll fluid machine of one embodiment. Fig. 2 is a cross-sectional perspective view showing the scroll fluid machine of Fig. 1. Fig. 3 is a cross-sectional view showing the scroll fluid machine of Fig. 1. Fig. 4 is a perspective view showing a rotating blade portion of the scroll fluid machine of Fig. 1. Fig. 5 is a cross-sectional view showing a modified scroll fluid machine. Fig. 6 is a cross-sectional view showing a scroll fluid machine of a comparative example.

[0024] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicated explanations will be omitted.

[0025] The scroll fluid machine 1 shown in Figures 1 and 2 is, for example, a scroll compressor that compresses a gas G such as air. The scroll fluid machine 1 may also be a scroll expander that expands the gas G. As shown in Figure 2, the scroll fluid machine 1 includes a fixed scroll section 2, an orbiting scroll section 3, and an orbiting jacket section 4. The scroll fluid machine 1 may also include a fixed jacket section 5 and an aftercooler section 6. The scroll fluid machine 1 compresses the gas G supplied from an intake port 11 in a plurality of spaces (hereinafter referred to as "compression chambers P") partitioned between the fixed scroll section 2 and the orbiting scroll section 3, and discharges the compressed gas G from a discharge port 12.

[0026] The fixed scroll portion 2 is fixed to a housing portion 7 that forms the outer shell of the scroll fluid machine 1. The orbiting scroll portion 3 and the orbiting jacket portion 4 are arranged inside the housing portion 7. The orbiting scroll portion 3 faces the fixed scroll portion 2. The orbiting jacket portion 4 is arranged on the opposite side of the orbiting scroll portion 3 from the fixed scroll portion 2. The orbiting scroll portion 3 is connected to a drive shaft 15 via the orbiting jacket portion 4. The drive shaft 15 is arranged inside another housing portion 8 that is connected to the housing portion 7 in the axial direction D1.

[0027] The drive shaft 15 includes a shaft main body 16 and an eccentric shaft portion 17. The eccentric shaft portion 17 extends from the shaft main body 16 along the axial direction D1 while being eccentric relative to the shaft main body 16. An eccentric axis A2 of the eccentric shaft portion 17 is offset from the rotational axis A1 of the shaft main body 16. The rotational axis A1 is an axis that passes through the center of the shaft main body 16. The eccentric axis A2 is an axis that passes through the center of the eccentric shaft portion 17. The rotational axis A1 and the eccentric axis A2 extend along the axial direction D1. In this specification, the "rotational axis" when simply referring to the "rotational axis of the drive shaft" means the rotational axis A1 of the shaft main body 16.

[0028] The drive shaft 15 is connected to a drive source such as a motor via a belt or the like. The drive shaft 15 is rotatably supported about a rotation axis A1 by a bearing 18. The eccentric shaft portion 17 is rotatably supported about an eccentric axis A2 by a bearing 19 located closer to the tip surface 15a than the bearing 18. When the drive shaft 15 rotates about the rotation axis A1, the eccentric shaft portion 17 orbits about the rotation axis A1. The orbiting scroll portion 3 orbits relative to the fixed scroll portion 2 due to the orbiting of the eccentric shaft portion 17. The orbiting scroll portion 3 is supported by a driven shaft 36. The driven shaft 36 is connected to the orbiting scroll portion 3 via the orbiting jacket portion 4.

[0029] The fixed scroll portion 2 has, for example, a cylindrical outer shape having a bottom. The fixed scroll portion 2 includes, for example, a fixed end plate 21 and a fixed wrap 22. The fixed end plate 21 includes, for example, a disk-shaped bottom wall portion 23 and a cylindrical outer peripheral wall portion 24 rising from the peripheral edge of the bottom wall portion 23. The bottom wall portion 23 includes, for example, a fixed main surface 23a and a fixed back surface 23b facing the opposite side to the fixed main surface 23a. The fixed main surface 23a faces the orbiting scroll portion 3 in the axial direction D1. The bottom wall portion 23 is formed with an intake port 11 for taking in gas G and a discharge port 12 for discharging compressed gas G. The outer peripheral wall portion 24 forms the outer peripheral wall of the fixed scroll portion 2.

[0030] The fixed wrap 22 is formed on the fixed main surface 23a of the fixed scroll portion 2. When viewed along the axial direction D1, the fixed wrap 22 has a so-called spiral shape. A compression chamber P is formed by the fixed wrap 22 and an orbiting wrap 32, which will be described later. When the scroll fluid machine 1 is a compressor, as in this embodiment, the compression chamber P moves from the outer circumferential side to the inner circumferential side while orbiting around the rotation axis A1 in accordance with the orbiting of the orbiting scroll portion 3. The volume of the compression chamber P decreases as it approaches the inner circumferential side. Finally, the compressed gas is discharged from a discharge port 12 formed in the bottom wall portion 23.

[0031] The orbiting scroll portion 3 includes, for example, an orbiting end plate 31 and an orbiting wrap 32. The orbiting end plate 31 has, for example, a disk shape. The orbiting end plate 31 includes, for example, a main orbiting surface 31a and an orbiting back surface 31b facing the opposite side to the main orbiting surface 31a. The main orbiting surface 31a faces the fixed scroll portion 2 in the axial direction D1. The orbiting back surface 31b is provided with a plurality of fins 35 for heat dissipation. The drive shaft 15 and the driven shaft 36 are connected to the orbiting back surface 31b via the orbiting jacket portion 4. The orbiting wrap 32 is formed on the main orbiting surface 31a of the orbiting scroll portion 3. The orbiting wrap 32 has a so-called spiral shape when viewed along the axial direction D1.

[0032] A portion of the inner peripheral surface of the orbiting wrap 32 contacts a portion of the outer peripheral surface of the fixed wrap 22. A portion of the outer peripheral surface of the orbiting wrap 32 contacts a portion of the inner peripheral surface of the fixed wrap 22. These contact areas move in a spiral pattern from the outer peripheral side toward the center around the rotation axis A1 as the orbiting wrap 32 orbits. A pair of adjacent contact areas defines one compression chamber P. The volume of the compression chamber P decreases as the compression chamber P moves from the outer peripheral side to the center, compressing the gas G.

[0033] Due to the effects of compression of the gas G, etc., a temperature rise occurs in the fixed scroll portion 2 and the orbiting scroll portion 3. Therefore, the scroll fluid machine 1 of this embodiment is provided with a cooling structure to suppress this temperature rise. In the scroll fluid machine 1, a refrigerant R (see FIG. 3 ) is supplied to the orbiting scroll portion 3 through the drive shaft 15, and the orbiting scroll portion 3 is cooled by the refrigerant R. In this embodiment, a case is illustrated in which the refrigerant R is cooling water, but the refrigerant R may be another cooling medium such as cooling oil.

[0034] 3 , the tip end P1 of the drive shaft 15 is inserted into the orbiting jacket portion 4 that covers the orbiting back surface 31 b of the orbiting scroll portion 3, and is connected to the orbiting scroll portion 3 via the orbiting jacket portion 4. The tip end P1 is the portion of the drive shaft 15 that is disposed inside the orbiting jacket portion 4, i.e., the portion of the drive shaft 15 that is accommodated in the internal space V between the orbiting scroll portion 3 and the orbiting jacket portion 4.

[0035] The tip portion P1 includes a tip surface 15a of the drive shaft 15. The tip surface 15a is an end surface located at the tip of the drive shaft 15 along the axial direction D1. The tip surface 15a faces the orbiting back surface 31b of the orbiting scroll section 3 in the axial direction D1 with a gap therebetween. In this specification, "facing" or "facing" includes a case where a first element faces (or is facing) a second element directly without any other element interposed therebetween, and a case where the first element faces (or is facing) a second element indirectly via another element interposed therebetween. The first element refers to any element (e.g., the tip surface 15a) that forms the scroll fluid machine 1. The second element refers to an element (e.g., the orbiting back surface 31b) that forms the scroll fluid machine 1 and is different from the first element.

[0036] The tip portion P1 includes a tip side surface 15b extending from the tip surface 15a along the axial direction D1 toward the opposite side to the swivel back surface 31b. The tip side surface 15b is accommodated in the internal space V together with the tip surface 15a. The outer portion P2 of the drive shaft 15, excluding the tip portion P1, is not accommodated in the internal space V but is disposed outside the swivel jacket portion 4. The outer portion P2 includes an outer side surface 15c extending along the axial direction D1 outside the swivel jacket portion 4. The tip portion P1 is, for example, a part of the eccentric shaft portion 17 of the drive shaft 15. The outer portion P2 is, for example, the remainder of the eccentric shaft portion 17 and the shaft main body 16. In this case, the entire tip portion P1 and a part of the outer portion P2 are included in the eccentric shaft portion 17, and the remainder of the outer portion P2 is included in the shaft main body 16.

[0037] The rotating blade portion 13 is attached to the tip side surface 15b of the tip portion P1. The rotating blade portion 13 is housed in the internal space V together with the tip portion P1. The rotating blade portion 13 extends radially outward from the tip portion P1 in the radial direction D2. The rotating blade portion 13 rotates integrally with the drive shaft 15 around the drive shaft 15. The radial direction D2 is a direction extending perpendicular to the eccentric axis A2 and is orthogonal to the axial direction D1. The outer side of the radial direction D2 refers to the direction in the radial direction D2 that moves away from the eccentric axis A2, and the inner side of the radial direction D2 refers to the direction in the radial direction D2 that moves toward the eccentric axis A2.

[0038] The rotating vane portion 13 faces the rotating back surface 31b of the rotating jacket portion 4 in the axial direction D1. The fins 35 are not provided on the portion of the rotating back surface 31b facing the rotating vane portion 13 to avoid interference between the fins 35 and the rotating vane portion 13. The fins 35 are provided only on the rotating back surface 31b outside the rotating vane portion 13 (see FIG. 2). For simplicity, the fins 35 are omitted from FIG. 3.

[0039] In this embodiment, the rotating blade section 13 has a configuration in which a spiral impeller and a vortex-type impeller are integrated. Specifically, the rotating blade section 13 has a spiral impeller (a plurality of first blades 132a, described later) on the inside in the radial direction D2 and a vortex-type impeller (a plurality of second blades 132b, described later) on the outside in the radial direction D2. In the rotating blade section 13 having such a configuration, the liquid (refrigerant R) is pressurized in the first spiral-type first blades 132a to prevent evaporation of the liquid, and the liquid is further pressurized in the second spiral-type second blades 132b. This allows the rotating blade section 13 to transport liquid that is likely to evaporate from the inside to the outside in the radial direction D2 without evaporating it. The rotating blade section 13 may be, for example, a spiral impeller, a vortex-type impeller, or a gas-liquid transfer impeller. For example, a volute-type impeller may be selected when the pressure loss of the refrigerant R is small. A vortex-type impeller may be selected when the pressure loss of the refrigerant R is large. A gas-liquid transfer-type impeller may be selected when air is mixed into the refrigerant R or when cavitation occurs in the refrigerant R.

[0040] As shown in Fig. 4, the rotary blade unit 13 includes a disk-shaped rotary base 131 and a plurality of blades 132 rising from a surface 131b of the rotary base 131. The rotary base 131 is formed with a mounting hole 131a into which the tip portion P1 (see Fig. 3) is inserted for mounting. The plurality of blades 132 includes a plurality of first blades 132a formed around the mounting hole 131a and a plurality of second blades 132b formed around the plurality of first blades 132a.

[0041] The first blades 132a are arranged around the mounting hole 131a in a circumferential direction D3, for example, and are formed in a spiral shape around the eccentric axis A2. The circumferential direction D3 is a direction along a ring centered on the eccentric axis A2. The height of each first blade 132a from the surface 131b is, for example, constant.

[0042] The second blades 132b are arranged further outward in the radial direction D2 (see FIG. 3) than the first blades 132a. The second blades 132b are arranged, for example, on the periphery of the rotary base 131. The second blades 132b are arranged, for example, along the circumferential direction D3 on the periphery of the rotary base 131 and extend linearly along the radial direction D2. The height of each second blade 132b from the surface 131b increases, for example, as it moves outward in the radial direction D2.

[0043] The number of second blades 132b is greater than the number of first blades 132a, for example. The spacing between each second blade 132b along the circumferential direction D3 is narrower than the spacing between each first blade 132a along the circumferential direction D3. The length of each second blade 132b is shorter than the length of each first blade 132a. The length of each second blade 132b is the length from the base end of the second blade 132b located at the innermost position in the radial direction D2 to the tip of the second blade 132b located at the outermost position in the radial direction D2. The length of each first blade 132a is the length from the base end of the first blade 132a located at the innermost position in the radial direction D2 to the tip of the first blade 132a located at the outermost position in the radial direction D2. Only the first blades 132a may be formed on the surface 131b of the rotating base 131, and the second blades 132b may be omitted.

[0044] 3, when the rotating vane unit 13 is attached to the tip end P1 of the drive shaft 15, the surface 131b of the rotating base 131 faces the orbiting back surface 31b of the orbiting scroll unit 3 in the axial direction D1. The back surface 131c of the rotating base 131 faces the opposite side to the orbiting back surface 31b. A refrigerant supply passage R1 and a refrigerant discharge passage R2 are formed inside the drive shaft 15 to which the rotating vane unit 13 is attached.

[0045] The refrigerant supply channel R1 is formed, for example, by a circular through-hole penetrating the drive shaft 15. The refrigerant supply channel R1 is a channel surrounded by the inner surface of the through-hole penetrating the drive shaft 15. The refrigerant supply channel R1 opens to the outer portion P2 of the drive shaft 15, passes through the interior of the drive shaft 15, and opens to the tip end P1 of the drive shaft 15. The refrigerant supply channel R1 is fluidly connected to the internal space V that accommodates the tip end P1. In this specification, "a first element is fluidly connected to a second element" means that the first element and the second element are spatially continuous so that the refrigerant R can flow between them. As described above, the "first element" refers to any element that forms the scroll fluid machine 1, and the "second element" refers to an element that forms the scroll fluid machine 1 but is different from the first element. The refrigerant supply channel R1 is formed, for example, at a position offset from the eccentric axis A2 inside the drive shaft 15 and extends linearly along the axial direction D1.

[0046] The refrigerant supply flow path R1 includes a supply inlet R1a that opens to the outer portion P2 and a supply outlet R1b that opens to the tip end portion P1. The supply inlet R1a is connected to an external refrigerant supply source via a pipe or the like, and the refrigerant R is introduced from the refrigerant supply source. The supply inlet R1a opens, for example, to the outer surface 15c of the outer portion P2. The supply inlet R1a may also open to the end surface of the drive shaft 15 opposite to the tip end surface 15a.

[0047] The supply outlet R1b is formed, for example, at a position on the tip portion P1 closer to the orbiting back surface 31b than to the rotation base 131. In this case, the distance in the axial direction D1 between the orbiting back surface 31b and the supply outlet R1b is shorter than the distance in the axial direction D1 between the orbiting back surface 31b and the surface 131b of the rotation base 131. The supply outlet R1b is formed, for example, on the tip surface 15a that faces the center of the orbiting scroll portion 3 in the axial direction D1, but may also be formed on the tip side surface 15b. The refrigerant R introduced into the supply inlet R1a flows out from the supply outlet R1b.

[0048] The refrigerant discharge passage R2 is formed, for example, by a circular through-hole that penetrates the drive shaft 15. The refrigerant discharge passage R2 is a passage surrounded by the inner surface of the through-hole that penetrates the drive shaft 15. The refrigerant discharge passage R2 opens at the tip end P1 of the drive shaft 15, passes through the inside of the drive shaft 15, and opens at the outer portion P2 of the drive shaft 15. The refrigerant discharge passage R2 is fluidly connected to the internal space V that accommodates the tip end P1. The refrigerant discharge passage R2 is formed at a position offset from the eccentric axis A2 inside the drive shaft 15. The refrigerant discharge passage R2 is disposed, for example, on the opposite side of the eccentric axis A2 from the refrigerant supply passage R1 inside the drive shaft 15, and extends linearly along the axial direction D1 alongside the refrigerant supply passage R1.

[0049] The refrigerant discharge flow path R2 includes a discharge inlet R2a that opens at the tip end P1 and a discharge outlet R2b that opens at the outer portion P2. The discharge inlet R2a is formed at a position on the tip end P1 farther from the rotating back surface 31b than the rotating base 131. In other words, the distance in the axial direction D1 between the rotating back surface 31b and the discharge inlet R2a is greater than the distance in the axial direction D1 between the rotating back surface 31b and the front surface 131b of the rotating base 131. The discharge inlet R2a is formed, for example, on the tip side surface 15b, but may also be formed on the tip surface 15a. The refrigerant R supplied from the supply outlet R1b flows into the discharge inlet R2a.

[0050] The discharge outlet R2b opens to the outer surface 15c of the drive shaft 15. For example, the discharge outlet R2b opens on the outer surface 15c on the opposite side of the rotation axis A1 from the supply inlet R1a. The refrigerant R that has flowed into the discharge inlet R2a is discharged from the discharge outlet R2b. The refrigerant R discharged from the discharge outlet R2b is discharged to the outside via piping or the like. The discharge outlet R2b may also open to the end face of the drive shaft 15 opposite the tip end face 15a.

[0051] 3 , the orbiting jacket portion 4 is attached to the eccentric shaft portion 17 so as to surround the tip portion P1 and the rotating vane portion 13, and is connected in the axial direction D1 to the peripheral edge portion of the orbiting scroll portion 3. The orbiting jacket portion 4 is formed, for example, separately from the orbiting scroll portion 3, but may also be formed integrally with the orbiting scroll portion 3.

[0052] The orbiting jacket portion 4 includes a cylindrical jacket main body portion 41 and a cylindrical insertion portion 42 having an outer diameter smaller than that of the jacket main body portion 41. The jacket main body portion 41 houses the tip portion P1 and the rotating blade portion 13, and is connected to the orbiting back surface 31b of the orbiting scroll portion 3. The insertion portion 42 is disposed on the opposite side of the jacket main body portion 41 from the orbiting scroll portion 3. An insertion hole 42a into which the tip portion P1 is inserted is formed in the insertion portion 42.

[0053] The orbiting jacket portion 4 includes a jacket inner surface 4a which, together with the orbiting back surface 31b of the orbiting scroll portion 3, forms an internal space V. The jacket inner surface 4a is a surface facing inward of the orbiting jacket portion 4 and is arranged to cover the orbiting back surface 31b with a gap therebetween. The internal space V is defined as a space surrounded by the orbiting back surface 31b and the jacket inner surface 4a. Another member may be interposed between the orbiting back surface 31b and the jacket inner surface 4a.

[0054] The jacket inner surface 4a includes a main body inner surface 41a inside the jacket main body portion 41 and an insertion inner surface 42b inside the insertion portion 42. The main body inner surface 41a includes an opposing surface 411 opposing the rotating back surface 31b, and an inner surface 412 connecting the rotating back surface 31b and the opposing back surface.

[0055] The opposing surface 411 is disposed in a position opposing the swirling back surface 31b across the rotating blade portion 13 in the axial direction D1. The opposing surface 411 is connected to the insertion inner surface 42b and extends along the radial direction D2. The opposing surface 411 is spaced apart from the rotating blade portion 13 in the axial direction D1. The inner surface 412 is disposed so as to surround the rotating blade portion 13. The inner surface 412 is spaced apart from the rotating blade portion 13 in the radial direction D2 and extends along the axial direction D1.

[0056] In a cross section (i.e., the cross section in FIG. 3 ) that includes the rotation axis A1 and passes through the discharge outlet R2b, the inner surface 412 includes a first inner surface portion 412a that faces the discharge outlet R2b in the radial direction D2, and a second inner surface portion 412b that is located on the opposite side of the first inner surface portion 412a. A step portion 413 that protrudes from the second inner surface portion 412b toward the rotating blade portion 13 is formed in the second inner surface portion 412b. A small gap is formed between the step portion 413 and the rotating blade portion 13 to avoid interference between the step portion 413 and the rotating blade portion 13. The step portion 413 narrows the gap between the second inner surface portion 412b and the rotating blade portion 13, thereby preventing the refrigerant R from moving through the gap.

[0057] The internal space V surrounded by the jacket inner surface 4a and the rotating back surface 31b includes, for example, a first spatial region V1, a second spatial region V2, and a third spatial region V3. The first spatial region V1 is a gap region formed between the rotating back surface 31b and the rotating base 131 in the axial direction D1. The first spatial region V1 is fluidly connected to a supply outlet R1b opening at the tip end surface 15a. The second spatial region V2 includes a gap region formed between the rotating base 131 and the opposing surface 411 in the axial direction D1, and a gap region formed between the insertion inner surface 42b of the insertion portion 42 and the drive shaft 15. The second spatial region V2 is fluidly connected to a discharge inlet R2a opening at the tip end side surface 15b. The third spatial region V3 is a gap region formed between the rotating base 131 and the inner surface 412 in the radial direction D2. The third spatial region V3 connects the first spatial region V1 and the second spatial region V2.

[0058] During operation of the scroll fluid machine 1, refrigerant R is introduced from an external supply source into a supply inlet R1a opening on the outer surface 15c of the drive shaft 15. The refrigerant R introduced into the supply inlet R1a passes through a refrigerant supply flow path R1 inside the drive shaft 15 and is supplied from a supply outlet R1b opening on the tip end surface 15a of the drive shaft 15 to an internal space V inside the orbiting jacket portion 4. The refrigerant R supplied from the supply outlet R1b is stored in the internal space V. In the internal space V, the tip end surface 15a of the drive shaft 15 faces the center of the orbiting back surface 31b of the orbiting scroll portion 3. Therefore, the refrigerant R flowing out from the supply outlet R1b on the tip end surface 15a actively cools the central portion of the orbiting scroll portion 3.

[0059] The rotating vane unit 13 attached to the tip end P1 of the drive shaft 15 rotates around the eccentric axis A2 while orbiting in accordance with the rotation of the drive shaft 15. By rotating around the eccentric axis A2, the rotating vane unit 13 sends the refrigerant R supplied from the tip end surface 15a to the outside of the drive shaft 15. The outside of the drive shaft 15 refers to the direction away from the rotation axis A1 of the drive shaft 15, i.e., the outside in the radial direction D2. As a result, the refrigerant R flows along the radial direction D2 from the tip end P1 toward the inner surface 412 of the orbiting jacket unit 4 in the first spatial region V1. At this time, the refrigerant R that comes into contact with the central portion of the orbiting scroll unit 3 comes into contact with the orbiting scroll unit 3 from the central portion to the outer periphery. As a result, the entire orbiting scroll unit 3 is cooled by the refrigerant R.

[0060] The refrigerant R that flows outward in the radial direction D2 in the first spatial region V1 flows through the third spatial region V3 into the second spatial region V2 in response to the rotation of the rotating blade portion 13. At this time, the gap between the second inner surface portion 412b of the swirling jacket portion 4 and the rotating blade portion 13 is blocked by the step portion 413. Therefore, the refrigerant R moves to the second spatial region V2 through the gap between the first inner surface portion 412a opposite to the second inner surface portion 412b and the rotating blade portion 13. The refrigerant R that has moved to the second spatial region V2 moves inward in the radial direction D2 in response to the rotation of the rotating blade portion 13 and toward the tip side surface 15b of the drive shaft 15. The refrigerant R that has flowed into the second spatial region V2 flows into a discharge inlet R2a that opens at the tip side surface 15b, passes from the discharge inlet R2a through a refrigerant discharge flow path R2, and is discharged to the outside from a discharge outlet R2b.

[0061] In this way, the rotating vane section 13 forms a flow in the internal space V that guides the refrigerant R from the supply outlet R1b of the refrigerant supply passage R1 to the discharge inlet R2a of the refrigerant discharge passage R2. This allows the refrigerant R to flow smoothly from the refrigerant supply passage R1 to the refrigerant discharge passage R2. This flow of the refrigerant R promotes heat exchange between the refrigerant R and the orbiting scroll section 3, thereby efficiently cooling the orbiting scroll section 3.

[0062] 2, in the internal space V to which the refrigerant R is supplied, a shaft seal 45 is disposed adjacent to the bearing 18 that supports the eccentric shaft 17 (i.e., between the rotating vane 13 and the bearing 18 in the axial direction D1), and the shaft seal 45 prevents the refrigerant R from moving toward the bearing 18. For simplicity, the bearing 18 and the shaft seal 45 are not shown in FIG.

[0063] 2, the insertion portion 42 of the rotating jacket portion 4 is formed to surround the bearing 18 that supports the eccentric shaft portion 17, and holds the bearing 18. Therefore, the insertion portion 42 functions as a bearing holder that holds the bearing 18. In other words, the rotating jacket portion 4 has the function of forming an internal space V that stores the refrigerant R and the function of holding the bearing 18.

[0064] As shown in Fig. 2, the fixed jacket portion 5 is disposed on the opposite side of the fixed scroll portion 2 from the orbiting scroll portion 3. The fixed jacket portion 5 faces the fixed back surface 23b of the fixed scroll portion 2 and is connected to the fixed scroll portion 2. The fixed jacket portion 5 forms an internal space between the fixed jacket portion 5 and the fixed scroll portion 2 for storing a refrigerant R for cooling the fixed jacket portion 5. The fixed jacket portion 5 is formed, for example, separately from the fixed scroll portion 2, but may also be formed integrally with the fixed scroll portion 2.

[0065] The aftercooler section 6 is disposed on the opposite side of the fixed jacket section 5 from the fixed scroll section 2. The aftercooler section 6 faces the fixed scroll section 2 across the fixed jacket section 5. The aftercooler section 6 cools the gas G compressed by the fixed scroll section 2 and the orbiting scroll section 3 to a preset temperature. The gas G cooled by the aftercooler section 6 is discharged to the outside of the aftercooler section 6 through piping or the like.

[0066] The effects of the scroll fluid machine 1 described above will be explained together with the problems of the comparative example.

[0067] In the scroll fluid machine 100 of the comparative example shown in Fig. 6, the drive shaft 115 is not formed with a refrigerant supply passage R101 or a refrigerant discharge passage R102, but rather, the refrigerant supply passage R101 and the refrigerant discharge passage R102 are formed in two driven shafts 135, 136 that support the orbiting motion of the orbiting scroll section 103. The two driven shafts 135, 136 are arranged on either side of the drive shaft 115 and are connected to the orbiting scroll section 103 via the orbiting jacket section 104. The driven shaft 135 is formed with a refrigerant supply passage R101. The driven shaft 136 on the opposite side to the driven shaft 135 is formed with a refrigerant discharge passage R102.

[0068] In the scroll fluid machine 100 of the comparative example, the refrigerant R100 is supplied to the internal space V100 between the orbiting jacket portion 104 and the orbiting scroll portion 103 from a refrigerant supply passage R101 formed in the driven shaft 135. The refrigerant R100 supplied to the internal space V100 from the refrigerant supply passage R101 of the driven shaft 136 comes into contact with the outer periphery of the orbiting scroll portion 103. The refrigerant R100 then passes through the center of the orbiting scroll portion 103 and flows toward the refrigerant discharge passage R102 on the opposite side of the driven shaft 135, and is discharged to the outside from the refrigerant discharge passage R102. During operation of the scroll fluid machine 100, high-pressure gas is generated in the center of the orbiting scroll portion 103, so that the temperature rise in the center of the orbiting scroll portion 103 tends to be particularly significant. However, in the scroll fluid machine 100 of the comparative example, the refrigerant flows from the outer periphery of the orbiting scroll section 103 through the center, making it difficult to actively cool the center of the orbiting scroll section 103, where the temperature is likely to rise significantly, and making it difficult to efficiently cool the orbiting scroll section 103 with refrigerant R100.

[0069] In contrast, in the scroll fluid machine 1 of this embodiment, a refrigerant supply passage R1 that supplies refrigerant R to the internal space V is formed in the drive shaft 15. With this configuration, the refrigerant R supplied from the refrigerant supply passage R1 to the internal space V can actively cool the central portion of the orbiting scroll section 3, where temperature increases are likely to be significant, thereby efficiently preventing temperature increases in the orbiting scroll section 3. Furthermore, in the scroll fluid machine 1, the rotating vane section 13 that rotates together with the drive shaft 15 to send the refrigerant R outward in the radial direction D2 is accommodated in the internal space V. In this case, the rotational driving force of the drive shaft 15 can be used to form a flow of refrigerant R from the central portion of the orbiting scroll section 3 to the outside, thereby efficiently cooling the orbiting scroll section 3 from the central portion to the outside. Therefore, the scroll fluid machine 1 can improve cooling performance.

[0070] As in the present embodiment, the refrigerant supply passage R1 may include a supply outlet R1b that opens at a position in the tip portion P1 closer to the orbiting back surface 31b than the rotation base 131. By locating the supply outlet R1b closer to the orbiting scroll section 3 in this manner, the cooling effect of the refrigerant R supplied from the supply outlet R1b on the central portion of the orbiting scroll section 3 can be enhanced.

[0071] As in this embodiment, the supply outlet R1b may open to the tip end surface 15a. The supply inlet R1a may open to the outer surface 15c of the drive shaft 15. When the supply outlet R1b opens to the tip end surface 15a in this manner, the distance between the supply outlet R1b and the orbiting scroll section 3 is further reduced, thereby further enhancing the cooling effect on the central portion of the orbiting scroll section 3. Furthermore, when the supply inlet R1a opens to the outer surface 15c, the possibility of the refrigerant supply channel R1 interfering with components around the drive shaft 15 is reduced, unlike when the supply inlet R1a opens to the end face of the drive shaft 15 opposite the tip end surface 15a. As a result, the degree of freedom in the layout of components around the drive shaft 15 can be increased.

[0072] As in this embodiment, at least a portion of the tip portion P1 may be an eccentric shaft portion 17 that is eccentric from the rotation axis A1 of the drive shaft 15. The rotating vane portion 13 may be provided on the eccentric shaft portion 17. In this case, a suitable mode can be obtained in which the flow of refrigerant R is formed from the center of the orbiting scroll portion 3 to the outside by utilizing the rotational driving force of the drive shaft 15.

[0073] As in the present embodiment, the rotating vane section 13 may include a rotating base 131 extending from the tip end P1, and a plurality of vanes 132 extending up from the rotating base 131 and arranged around the drive shaft 15. In this case, it is possible to easily obtain the rotating vane section 13 that sends the refrigerant R from the center of the orbiting scroll section 3 to the outside.

[0074] As in this embodiment, the rotating jacket portion 4 may include an insert portion 42 formed to surround the bearing 18 supporting the drive shaft 15 and hold the bearing 18. In this case, the rotating jacket portion 4 can have both the function of forming an internal space V through which the refrigerant R flows between the jacket inner surface 4 a and the rotating back surface 31 b, and the function of holding the bearing 18 supporting the drive shaft 15.

[0075] As in this embodiment, the drive shaft 15 is formed with a refrigerant discharge passage R2 aligned with the refrigerant supply passage R1, and the refrigerant discharge passage R2 may open to the tip end P1 and be fluidly connected to the internal space V to discharge the refrigerant R supplied to the internal space V. In this case, the refrigerant R that has exchanged heat with the orbiting scroll section 3 in the internal space V can be discharged to the outside from the refrigerant discharge passage R2 that opens to the tip end P1 of the drive shaft 15. This allows the use of the refrigerant R to improve cooling efficiency.

[0076] As in the present embodiment, the supply outlet R1b may open at a position on the tip end P1 closer to the back surface 31b than the rotating blade portion 13, and the discharge inlet R2a may open at a position on the tip end P1 farther from the back surface 31b than the rotating blade portion 13. In this case, the refrigerant R can be easily guided from the supply outlet R1b to the discharge inlet R2a by utilizing the flow formed in the internal space V as the rotating blade portion 13 rotates. This makes it easy to obtain the effect of improving cooling efficiency using the refrigerant R.

[0077] As in the present embodiment, the supply outlet R1b may be formed in the tip end surface 15a of the tip portion P1, which faces the orbiting back surface 31b. The discharge inlet R2a may be formed in the tip end side surface 15b of the tip portion P1, which extends from the tip end surface 15a to the side opposite the orbiting back surface 31b. When the supply outlet R1b of the refrigerant supply passage R1 opens to the tip end surface 15a in this manner, the distance between the supply outlet R1b and the orbiting scroll section 3 is further shortened, thereby further enhancing the cooling effect of the refrigerant R supplied from the supply outlet R1b on the central portion of the orbiting scroll section 3. Furthermore, when the discharge inlet R2a of the refrigerant discharge passage R2 opens to the tip end side surface 15b, the flow of refrigerant R formed in the internal space V due to the rotation of the rotating vane section 13 can be easily formed from the supply outlet R1b to the discharge inlet R2a, thereby easily achieving the effect of improving cooling efficiency using the refrigerant R.

[0078] As in this embodiment, the discharge outlet R2b may open to the outer surface 15c of the drive shaft 15. In this case, unlike when the discharge outlet R2b opens to the end surface of the drive shaft 15 opposite the tip surface 15a, the possibility that the refrigerant discharge flow path R2 will interfere with the components around the drive shaft 15 can be reduced. As a result, the degree of freedom in the layout of the components around the drive shaft 15 can be increased.

[0079] As in the present embodiment, the internal space V may include a first spatial region V1 formed between the swirling back surface 31b and the rotary base 131 and fluidically connected to the supply outlet R1b, a second spatial region V2 formed between the rotary base 131 and the opposing surface 411 and fluidically connected to the discharge inlet R2a, and a third spatial region V3 formed between the rotary base 131 and the inner surface 412 and connecting the first spatial region V1 and the second spatial region V2. In this case, a spatial region through which the refrigerant R can flow can be formed around the rotating blade portion 13, and the flow of the refrigerant R from the supply outlet R1b to the discharge inlet R2a can be easily formed by utilizing this spatial region.

[0080] As in the present embodiment, the inner surface 412 may include a first inner surface portion 412a facing the discharge outlet R2b and a second inner surface portion 412b located on the opposite side of the first inner surface portion 412a in a cross section including the rotation axis A1 and passing through the discharge outlet R2b. The second inner surface portion 412b may have a step portion 413 protruding toward the rotating blade portion 13. In this case, the step portion 413 can narrow the gap between the second inner surface portion 412b and the rotating blade portion 13, thereby preventing the refrigerant R from moving through the gap. As a result, the refrigerant R supplied from the supply outlet R1b can easily flow through the gap between the first inner surface portion 412a and the rotating blade portion 13 to the discharge inlet R2a. This allows the refrigerant R to be easily guided from the supply outlet R1b to the discharge inlet R2a.

[0081] As in the present embodiment, a shaft seal 45 that prevents the refrigerant R from moving toward the bearing 18 may be provided in the internal space V at a position adjacent to the bearing 18 that supports the drive shaft 15. In this case, even when cooling water is used as the refrigerant R, the shaft seal 45 can prevent the cooling water from contacting the bearing 18, thereby avoiding malfunctions of the bearing 18 due to the cooling water contacting the bearing 18.

[0082] The scroll fluid machine of the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention.

[0083] <Modification> As shown in Fig. 5, the refrigerant discharge passage R2A does not necessarily have to be formed in the drive shaft 15. In the example shown in Fig. 5, only the refrigerant supply passage R1 is formed in the drive shaft 15. The refrigerant discharge passage R2A is formed in the orbiting scroll portion 3A and the fixed scroll portion 2A.

[0084] The refrigerant discharge passage R2A is formed by a circular through-hole extending from the orbiting scroll portion 3A to the fixed scroll portion 2A. The refrigerant discharge passage R2A opens to the orbiting back surface 31b of the orbiting scroll portion 3A. The refrigerant discharge passage R2A passes through the orbiting scroll portion 3A and the fixed scroll portion 2A and opens to the fixed back surface 23b of the fixed scroll portion 2A. The refrigerant discharge passage R2A is fluidly connected to the internal space V inside the orbiting jacket portion 4A.

[0085] The orbiting jacket portion 4A of the scroll fluid machine 1A is formed with not only a step portion 413 protruding from the second inner surface portion 412b but also a step portion 414 protruding from the first inner surface portion 412a. The step portion 414 protrudes from the first inner surface portion 412a toward the rotating vane portion 13. A small gap is formed between the step portion 414 and the rotating vane portion 13 to prevent interference between the step portion 414 and the rotating vane portion 13. The step portion 414 narrows the gap between the first inner surface portion 412a and the rotating vane portion 13, thereby preventing the refrigerant R from moving through the gap.

[0086] The refrigerant discharge flow passage R2A includes a discharge inlet R2c that opens to the orbiting back surface 31b and a discharge outlet R2d that opens to the fixed back surface 23b. The discharge inlet R2c is formed radially outward from a portion of the orbiting back surface 31b that faces the rotating vane portion 13. The discharge outlet R2d is formed at a position on the fixed back surface 23b that faces the discharge inlet R2c in the axial direction D1. The refrigerant discharge flow passage R2A extends, for example, from the discharge inlet R2c to the discharge outlet R2d along the axial direction D1. The refrigerant discharge flow passage R2A is formed, for example, in an outer peripheral protrusion 25 that extends from the fixed main surface 23a toward the orbiting main surface 31a at the outer periphery of the fixed scroll portion 2A. A seal may be formed around the outer peripheral protrusion 25 to prevent leakage of the refrigerant R from the refrigerant discharge flow passage R2A.

[0087] The outer peripheral protrusion 25, in which the refrigerant discharge passage R2A is formed, is formed outside the outer peripheral wall portion 24 that surrounds the compression chamber P in which the gas G is compressed. A dust seal portion 24a is attached to the outer peripheral wall portion 24 to prevent the intrusion of dust and the like from the outside. The dust seal portion 24a protrudes from the outer peripheral wall portion 24 and is in contact with the main swirling surface 31a.

[0088] The fixed back surface 23b is formed with a fixed inlet G2a for taking in the gas G to be compressed and a fixed discharge port G2b for discharging the compressed gas G. The fixed inlet G2a and the fixed discharge port G2b are openings that open at different positions on the fixed back surface 23b. The fixed inlet G2a is formed, for example, in the outer periphery of the fixed scroll portion 2A. The fixed discharge port G2b is formed, for example, in the center of the fixed scroll portion 2A. The fixed inlet G2a is formed, for example, in a position on the fixed back surface 23b opposite the discharge outlet R2d across the rotation axis A1 of the drive shaft 15. The fixed inlet G2a is disposed inside the outer periphery wall portion 24 of the fixed scroll portion 2A. The fixed inlet G2a is fluidly connected to a compression chamber P for compressing the gas G. The gas G taken into the fixed inlet G2a is compressed in the compression chamber P. The compressed gas G is discharged from the fixed discharge port G2b.

[0089] The fixed jacket portion 5A includes a jacket main surface 5a facing the fixed back surface 23b and a jacket back surface 5b facing the opposite side to the jacket main surface 5a. The jacket main surface 5a is formed with a refrigerant inlet R5a through which the refrigerant R flows in and a gas inlet G5a through which the gas G flows in. The jacket back surface 5b is formed with a refrigerant outlet R5b through which the refrigerant R flows out from the refrigerant inlet R5a and a gas outlet G5b through which the gas G flows out from the gas inlet G5a.

[0090] The refrigerant inlet R5a opens at a position on the jacket main surface 5a opposite the discharge outlet R2d. The refrigerant inlet R5a is fluidly connected to the refrigerant discharge flow path R2A. The refrigerant inlet R5a is formed, for example, on the outer periphery of the fixed jacket portion 5A. The refrigerant R discharged from the discharge outlet R2d flows into the refrigerant inlet R5a. The refrigerant outlet R5b is formed on the jacket back surface 5b at a position opposite the refrigerant inlet R5a across the rotation axis A1 of the drive shaft 15. The refrigerant outlet R5b is fluidly connected to the refrigerant inlet R5a via a flow path formed inside the fixed jacket portion 5A. The refrigerant R that flowed into the refrigerant inlet R5a flows out from the refrigerant outlet R5b.

[0091] The gas inlet G5a opens at a position on the jacket main surface 5a facing the fixed discharge port G2b. The gas inlet G5a is fluidly connected to the compression chamber P. The gas inlet G5a is formed, for example, in the center of the fixed jacket portion 5A. The gas G discharged from the fixed discharge port G2b flows into the gas inlet G5a. The gas outlet G5b opens at a position on the jacket back surface 5b facing the gas inlet G5a. The gas outlet G5b is fluidly connected to the gas inlet G5a via a flow path formed inside the fixed jacket portion 5A. The gas inlet G5a and the gas outlet G5b are formed, for example, in the center of the fixed jacket portion 5A. The gas G that flows into the gas inlet G5a flows out from the gas outlet G5b.

[0092] The aftercooler section 6A includes an aftercooler main surface 6a facing the jacket main surface 5a and an aftercooler back surface 6b facing the opposite side to the aftercooler main surface 6a. The aftercooler main surface 6a is formed with a refrigerant inlet R6a through which the refrigerant R flows in from the refrigerant outlet R6b and a gas inlet G6a through which the gas G flows in from the gas outlet G5b. The aftercooler back surface 6b is formed with a refrigerant outlet R6b through which the refrigerant R flows out from the refrigerant inlet R6a and a gas outlet G6b through which the gas G flows out from the gas inlet G6a.

[0093] The refrigerant inlet R6a opens at a position on the aftercooler main surface 6a opposite the refrigerant outlet R5b. The refrigerant inlet R6a is formed, for example, on the outer periphery of the aftercooler section 6A. The refrigerant R flowing out from the refrigerant outlet R5b flows into the refrigerant inlet R6a. The refrigerant outlet R6b is formed at a position on the aftercooler back surface 6b opposite the refrigerant inlet R6a. The refrigerant outlet R6b is fluidly connected to the refrigerant inlet R6a via a flow path formed inside the aftercooler section 6A. The refrigerant R flowing out from the refrigerant outlet R6b is discharged to the outside.

[0094] The gas inlet G6a opens at a position on the aftercooler main surface 6a opposite the gas outlet G5b. The gas inlet G6a is formed, for example, in the center of the aftercooler section 6A. The gas G discharged from the gas outlet G5b flows into the gas inlet G6a. The gas outlet G6b is formed on the outer periphery of the aftercooler section 6A on the opposite side to the refrigerant outlet R6b across the rotational axis A1 of the drive shaft 15. The gas outlet G6b is fluidly connected to the gas inlet G6a via a flow path formed inside the aftercooler section 6A. The gas G flows out from the gas outlet G6b.

[0095] During operation of the scroll fluid machine 1A, refrigerant R is introduced from an external supply source into a supply inlet R1a of a refrigerant supply passage R1, which opens on the outer surface 15c of the drive shaft 15. The refrigerant R introduced into the supply inlet R1a passes through the refrigerant supply passage R1 inside the drive shaft 15 and is supplied from a supply outlet R1b of the refrigerant supply passage R1, which opens on the tip end surface 15a of the drive shaft 15, to an internal space V inside the orbiting jacket portion 4A. The refrigerant R supplied from the supply outlet R1b is stored in the internal space V. In the internal space V, the tip end surface 15a of the drive shaft 15 faces the center of the orbiting back surface 31b of the orbiting scroll portion 3A. Therefore, the refrigerant R flowing out from the supply outlet R1b of the tip end surface 15a contacts and cools the center of the orbiting scroll portion 3A.

[0096] The rotating vane section 13 attached to the tip end P1 of the drive shaft 15 rotates around the eccentric axis A2 while orbiting in accordance with the rotation of the drive shaft 15. By rotating around the eccentric axis A2, the rotating vane section 13 sends the refrigerant R supplied from the tip end surface 15a outward in the radial direction D2. As a result, in the first spatial region V1, the refrigerant R flows along the radial direction D2 from the tip end P1 toward the inner surface of the orbiting jacket section 4A. At this time, the refrigerant R that comes into contact with the central portion of the orbiting scroll section 3A comes into contact with the entire orbiting scroll section 3A from the central portion to the outer periphery. As a result, the entire orbiting scroll section 3A is cooled by the refrigerant R.

[0097] The refrigerant R that flows outward in the radial direction D2 in the first spatial region V1 flows into the discharge inlet R2c that opens into the rotating back surface 31b in response to the rotation of the rotating blade portion 13. At this time, the gap between the inner surface 412 and the rotating blade portion 13 is blocked by the step portions 413, 414. Therefore, the refrigerant R flows straight toward the discharge inlet R2c in the first spatial region V1 without flowing around into the second spatial region V2. The refrigerant R that flows into the discharge inlet R2c passes through the refrigerant discharge flow path R2A and is discharged from the discharge outlet R2d. The refrigerant R that is discharged from the discharge outlet R2d passes through the fixed jacket portion 5A and the aftercooler portion 6A and is discharged to the outside.

[0098] In this way, the rotating vane portion 13 forms a flow in the internal space V that guides the refrigerant R from the supply outlet R1b of the refrigerant supply passage R1 to the discharge inlet R2c of the refrigerant discharge passage R2A. This allows the refrigerant R to flow smoothly from the refrigerant supply passage R1 to the refrigerant discharge passage R2A. This flow of the refrigerant R promotes heat exchange between the refrigerant R and the orbiting scroll portion 3A, thereby efficiently cooling the orbiting scroll portion 3A.

[0099] As in the scroll fluid machine 1A, by forming the refrigerant discharge passage R2A in the orbiting scroll section 3A and the fixed scroll section 2A, both the orbiting scroll section 3A and the fixed scroll section 2A can be efficiently cooled. Furthermore, as in the scroll fluid machine 1A, when the refrigerant discharge passage R2A opens at a position on the fixed back surface 23b opposite the fixed inlet G2a across the rotation axis A1, it is possible to reduce the possibility of the gas G taken in at the fixed inlet G2a and the refrigerant R flowing through the refrigerant discharge passage R2A being mixed together.

[0100] The scroll fluid machine according to the present invention is not limited to the above-described embodiment and modifications, and various modifications are possible without departing from the spirit and scope of the present invention. The configurations and methods of the above-described embodiment and modifications may be arbitrarily adopted and combined. For example, the configurations and methods of the embodiment may be applied to the configurations and methods of the modifications. For example, in the above-described embodiment and modifications, the scroll fluid machine includes a stationary jacket portion and an aftercooler portion. The scroll fluid machine does not necessarily include a stationary jacket portion and an aftercooler portion. In the above-described embodiment and modifications, the tip end of the drive shaft accommodated in the internal space between the orbiting scroll portion and the orbiting jacket portion is a portion of the eccentric shaft portion including the tip surface. The tip end of the drive shaft accommodated in the internal space may be the entire eccentric shaft portion, or may be a portion including the eccentric shaft portion and a portion of the shaft main body. The rotating vane portion is not limited to an impeller, and may have another form as long as it can send refrigerant to the outside of the drive shaft.

[0101] [Additional Note] The present invention includes the following configurations.

[0102] The present disclosure is [1] "a scroll fluid machine comprising: a fixed scroll portion including a fixed main surface on which a spiral-shaped fixed wrap is formed, and a fixed back surface facing the opposite side to the fixed main surface; an orbiting scroll portion including an orbiting main surface on which a spiral-shaped orbiting wrap is formed and facing the fixed wrap, and an orbiting back surface facing the opposite side to the orbiting main surface; an orbiting jacket portion including an inner jacket surface covering the orbiting back surface and connected to the orbiting scroll portion; and a drive shaft connected to the orbiting scroll portion via the orbiting jacket portion and orbiting the orbiting scroll portion relative to the fixed scroll portion, wherein a tip portion of the drive shaft is inserted into the orbiting jacket portion and housed in an internal space formed between the orbiting back surface and the inner jacket surface, the drive shaft having a refrigerant supply passage that opens to the tip portion and is fluidly connected to the internal space and supplies refrigerant to the internal space, and the internal space houses a rotating vane portion that is provided at the tip portion and rotates together with the drive shaft to send the refrigerant to the outside of the drive shaft."

[0103] The present disclosure is [2] "A scroll fluid machine as described in [1], wherein the rotating blade portion includes a rotating base portion extending from the tip portion, and the refrigerant supply flow path includes a supply outlet opening at a position in the tip portion closer to the rear surface of the rotating shaft than the rotating base portion."

[0104] The present disclosure provides, [3] the scroll fluid machine according to [1], wherein "the supply outlet opens into a tip end surface of the tip portion that faces the orbiting back surface, and the refrigerant supply flow path further includes a supply inlet that opens into an outer surface of the drive shaft that is disposed outside the orbiting jacket portion and that introduces the refrigerant into the refrigerant supply flow path."

[0105] The present disclosure is [4] "A scroll fluid machine according to any one of [1] to [3], wherein at least a portion of the tip end is an eccentric shaft portion that is eccentric from the rotation axis of the drive shaft, and the rotating vane portion is provided on the eccentric shaft portion."

[0106] The present disclosure is [5] "A scroll fluid machine according to any one of [1] to [4], wherein the rotating blade portion includes a rotating base portion extending from the tip portion, and a plurality of blades arranged around the drive shaft and rising from the rotating base portion."

[0107] The present disclosure is [6] "A scroll fluid machine described in any one of [1] to [5], wherein the rotating jacket portion includes a bearing holding portion formed to surround a bearing supporting the drive shaft and holding the bearing."

[0108] The present disclosure is [7] "A scroll fluid machine according to any one of [1] to [6], wherein the drive shaft is formed with a refrigerant discharge flow path aligned with the refrigerant supply flow path, the refrigerant discharge flow path opens to the tip end portion and is fluidly connected to the internal space, and discharges the refrigerant supplied to the internal space."

[0109] The present disclosure is [8] "A scroll fluid machine according to [7], wherein the rotating vane portion includes a rotating base portion extending from the tip portion, the refrigerant supply flow path includes a supply outlet opening at a position in the tip portion closer to the back surface of the rotating rotor than the rotating base, and the refrigerant discharge flow path includes a discharge inlet opening at a position in the tip portion farther from the back surface of the rotating rotor than the rotating base."

[0110] The present disclosure is [9] "A scroll fluid machine according to [8], wherein the supply outlet is formed in a tip surface of the tip portion that faces the back surface of the orbital, and the discharge inlet is formed in a tip side surface of the tip portion that extends from the tip surface to the side opposite the back surface of the orbital."

[0111] The present disclosure is

[10] "A scroll fluid machine as described in [9], wherein the refrigerant discharge flow path further includes a discharge outlet that opens to an outer surface of the drive shaft that is positioned outside the rotating jacket portion and that discharges the refrigerant that has flowed into the refrigerant discharge flow path."

[0112] The present disclosure is

[11] "A scroll fluid machine according to

[10] , wherein the inner surface of the jacket includes an opposing surface facing the rotating back surface, and an inner surface connecting the rotating back surface and the opposing surface and surrounding the rotating blade portion, and the internal space includes a first spatial region formed between the rotating back surface and the rotating base and fluidly connected to the supply outlet, a second spatial region formed between the rotating base and the opposing surface and fluidly connected to the discharge inlet, and a third spatial region formed between the rotating base and the inner surface and connecting the first spatial region and the second spatial region."

[0113] The present disclosure is

[12] "A scroll fluid machine as described in

[11] , wherein the inner surface includes, in a cross section including the rotation axis of the drive shaft and passing through the discharge outlet, a first inner surface portion facing the discharge outlet and a second inner surface portion located on the opposite side of the first inner surface portion, and a step portion protruding toward the rotating blade portion is formed on the second inner surface portion."

[0114] The present disclosure is

[13] "A scroll fluid machine according to any one of [1] to [6], wherein the orbiting scroll section and the fixed scroll section are formed with a refrigerant discharge flow path extending from the orbiting scroll section to the fixed scroll section, the refrigerant discharge flow path opening to the orbiting back surface and fluidly connected to the internal space, and discharging the refrigerant supplied to the internal space."

[0115] The present disclosure is

[14] "A scroll fluid machine according to

[13] , wherein a fixed intake port for taking in gas to be compressed or expanded is formed on the fixed back surface at a position offset from the rotation axis of the drive shaft, and the refrigerant discharge flow path opens at a position on the fixed back surface opposite the fixed intake port across the rotation axis."

[0116] The present disclosure is

[15] "A scroll fluid machine described in any one of [1] to

[14] , wherein a shaft seal portion that prevents the refrigerant from moving to the bearing is provided in the internal space at a position adjacent to the bearing that supports the drive shaft."

[0117] 1, 1A...Scroll fluid machine, 2, 2A...Fixed scroll portion, 3, 3A...Orbiting scroll portion, 4, 4A...Orbiting jacket portion, 4a...Jacket inner surface, 13...Rotating blade portion, 15, 115...Drive shaft, 15a...Tip surface, 15b...Tip side surface, 15c...Outer surface, 17...Eccentric shaft portion, 18, 19...Bearing, 22...Fixed wrap, 23a...Fixed main surface, 23b...Fixed back surface, 31a...Orbiting main surface, 31b...Orbiting back surface, 32...Orbiting wrap, 45...Shaft seal portion, 131...Rotating base portion, 132...Blade 411...Opposing surface, 412...Inner surface, 412a...First inner surface part, 412b...Second inner surface part, 413,414...Step part, A1...Rotation axis, A2...Eccentric axis, D2...Radial direction, G...Gas, G2a...Fixed intake port, P1...Tip part, R...Refrigerant, R 1... Refrigerant supply channel, R1a... Supply inlet, R1b... Supply outlet, R2, R2A... Refrigerant discharge channel, R2a, R2c... Discharge inlet, R2b, R2d... Discharge outlet, V... Internal space, V1... First spatial region, V2... Second spatial region, V3... Third spatial region.

Claims

1. A scroll fluid machine comprising: a fixed scroll section including a fixed main surface on which a spiral-shaped fixed wrap is formed, and a fixed back surface facing the opposite side to the fixed main surface; an orbiting scroll section including an orbiting main surface on which a spiral-shaped orbiting wrap is formed facing the fixed wrap, and an orbiting back surface facing the opposite side to the orbiting main surface; an orbiting jacket section including an inner jacket surface covering the orbiting back surface and connected to the orbiting scroll section; and a drive shaft connected to the orbiting scroll section via the orbiting jacket section and orbiting the orbiting scroll section relative to the fixed scroll section, wherein a tip end of the drive shaft is inserted into the orbiting jacket section and housed in an internal space formed between the orbiting back surface and the inner jacket surface, the drive shaft having a refrigerant supply flow path that opens to the tip end and is fluidly connected to the internal space and supplies refrigerant to the internal space, and a rotating vane section provided at the tip end that rotates together with the drive shaft to send the refrigerant to the outside of the drive shaft.

2. A scroll fluid machine as described in claim 1, wherein the rotating blade portion includes a rotating base portion extending from the tip portion, and the refrigerant supply flow path includes a supply outlet opening at a position on the tip portion closer to the back surface of the rotating shaft than the rotating base portion.

3. A scroll fluid machine as described in claim 2, wherein the supply outlet opens to a tip surface of the tip portion facing the back surface of the swivel, and the refrigerant supply flow path opens to an outer surface of the drive shaft positioned outside the swivel jacket portion, and further includes a supply inlet for introducing the refrigerant into the refrigerant supply flow path.

4. A scroll fluid machine as claimed in any one of claims 1 to 3, wherein at least a portion of the tip is an eccentric shaft portion that is eccentric from the rotation axis of the drive shaft, and the rotating vane portion is provided on the eccentric shaft portion.

5. A scroll fluid machine as described in any one of claims 1 to 3, wherein the rotating blade portion includes a rotating base portion extending from the tip portion, and a plurality of blades arranged to rise from the rotating base portion and arranged around the drive shaft.

6. A scroll fluid machine according to any one of claims 1 to 3, wherein the orbiting jacket portion includes a bearing holding portion formed to surround a bearing that supports the drive shaft and holds the bearing.

7. A scroll fluid machine as claimed in any one of claims 1 to 3, wherein the drive shaft is formed with a refrigerant discharge flow path aligned with the refrigerant supply flow path, the refrigerant discharge flow path opening at the tip end and fluidly connected to the internal space, and discharging the refrigerant supplied to the internal space.

8. A scroll fluid machine as described in claim 7, wherein the rotating blade portion includes a rotating base portion extending from the tip portion, the refrigerant supply flow path includes a supply outlet opening at a position in the tip portion closer to the back surface of the rotating shaft than the rotating base portion, and the refrigerant discharge flow path includes a discharge inlet opening at a position in the tip portion farther from the back surface of the rotating shaft than the rotating base portion.

9. A scroll fluid machine as described in claim 8, wherein the supply outlet is formed on the tip surface of the tip portion facing the back surface of the orbital, and the discharge inlet is formed on the tip side surface of the tip portion extending from the tip surface to the opposite side of the back surface of the orbital.

10. A scroll fluid machine as described in claim 9, wherein the refrigerant discharge flow path further includes a discharge outlet that opens onto an outer surface of the drive shaft positioned outside the rotating jacket portion and discharges the refrigerant that has flowed into the refrigerant discharge flow path.

11. A scroll fluid machine as described in claim 10, wherein the inner surface of the jacket includes an opposing surface facing the rotating back surface, and an inner surface connecting the rotating back surface and the opposing surface and surrounding the rotating blade portion, and the internal space includes: a first spatial region formed between the rotating back surface and the rotating base and fluidly connected to the supply outlet, a second spatial region formed between the rotating base and the opposing surface and fluidly connected to the discharge inlet, and a third spatial region formed between the rotating base and the inner surface and connecting the first spatial region and the second spatial region.

12. A scroll fluid machine as described in claim 11, wherein the inner surface includes, in a cross section including the rotation axis of the drive shaft and passing through the discharge outlet, a first inner surface portion facing the discharge outlet and a second inner surface portion located on the opposite side of the first inner surface portion, and a step portion protruding toward the rotating blade portion is formed on the second inner surface portion.

13. A scroll fluid machine as described in any one of claims 1 to 3, wherein the orbiting scroll section and the fixed scroll section are formed with a refrigerant discharge flow path extending from the orbiting scroll section to the fixed scroll section, the refrigerant discharge flow path opening to the back surface of the orbiting scroll and fluidly connected to the internal space, and discharging the refrigerant supplied to the internal space.

14. A scroll fluid machine as described in claim 13, wherein a fixed intake port for taking in gas to be compressed or expanded is formed at a position on the fixed back surface offset from the rotational axis of the drive shaft, and the refrigerant discharge flow path opens at a position on the fixed back surface opposite the fixed intake port across the rotational axis.

15. A scroll fluid machine according to any one of claims 1 to 3, wherein a shaft seal is provided in the internal space at a position adjacent to a bearing supporting the drive shaft to prevent the refrigerant from moving toward the bearing.

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