JP2011132927A - Scroll fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide structure for reducing a heat loss of working fluid, in a scroll fluid machine utilized as an expander. <P>SOLUTION: The scroll fluid machine of an outer periphery drive type includes: a body cover (a front side cover 4 and a back side cover 5) totally covering an oscillating scroll 1, two fixed scrolls 2, 3, and two cranks, excluding supply ports 20a, 30a, working fluid discharge ports, and two crankshafts, and which are disposed distantly from the oscillation scroll 1 and the two fixed scrolls 2, 3; and a premixing chamber having working fluid passages extended from the supply ports 20a, 30a inside the body cover to the outside of the body cover. An inlet-side clearance L1 is formed between the body cover and the premixing chamber so as to prevent abutment of the body cover on the premixing chamber. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a scroll type fluid machine that can be used as a compressor or an expander.

  The scroll type fluid machine can be used as a compressor or an expander. In the scroll type fluid machine, a compression chamber or an expansion chamber is formed between the fixed scroll and the swing scroll. The scroll compressor reduces the volume of the compression chamber by swinging the swing scroll with respect to the fixed scroll. As a result, the fluid in the compression chamber is compressed. The outer peripheral drive type scroll compressor includes a plurality of cranks for swinging the swing scroll with respect to the fixed scroll. Each crank is provided on the outer peripheral side of the orbiting scroll.

  Patent Documents 1, 2, and 3 disclose a technique for solving a thermal problem in an outer peripheral drive type scroll compressor. Patent Document 1 allows thermal expansion of an orbiting scroll (orbiting scroll) by providing an elastic body on one crank. For this reason, even if the relative position of the rocking scroll and the fixed scroll changes due to the thermal expansion of the rocking scroll, the rocking scroll can rotate smoothly. Patent Document 2 also solves the same problem as Patent Document 1. Patent Document 2 allows thermal expansion of an orbiting scroll (orbiting scroll) by slidably supporting a bearing of one crank. Patent Document 3 suppresses thermal expansion of the orbiting scroll by cooling both the fixed scroll and the orbiting scroll (orbiting scroll). Since the orbiting scroll does not thermally expand, the orbiting scroll can rotate smoothly.

JP 2000-27773 A Japanese Patent Laid-Open No. 2001-227481 Japanese Patent No. 3781564

  When the scroll type fluid machine is used as an expander, the supplied working fluid loses pressure, but the scroll type fluid machine as the expander (scroll type expander) obtains power for driving the crank. That is, pressure energy is converted to rotational energy. Here, the higher the working fluid temperature, the higher the power conversion efficiency. For this reason, when the calorie | heat amount of a working fluid is radiated | emitted via the component of a scroll type expander, the efficiency of power conversion will fall. For this reason, in the scroll type expander, it is preferable that heat radiation from the working fluid can be prevented.

  Therefore, the present invention provides a structure that can reduce the heat loss of the working fluid in a scroll type fluid machine used as an expander.

  According to the present invention, a fixed scroll is disposed on each side of the swing scroll in a swing center axis of the swing scroll with respect to the fixed scroll, and a plurality of driving the swing scroll outside the fixed scroll in the radial direction of the center axis. An outer peripheral drive type scroll type fluid machine in which a crank is disposed and a supply port of a working fluid formed in the fixed scroll is disposed on the central axis, the supply port being formed in the fixed scroll Except for the working fluid discharge port and the crank output shaft, the swing scroll, the two fixed scrolls, and the plurality of cranks are entirely covered, and disposed apart from the swing scroll and the two fixed scrolls. A main body cover and a working fluid passage extending from the supply port inside the main body cover to the outside of the main body cover; And mouth member provided with a, so as not to contact the body cover and the inlet member, the inlet-side gap is formed between the body cover and the inlet member.

  According to the present invention, the inlet member that contacts the working fluid and the main body cover are thermally blocked. As a result, it is possible to prevent the high temperature working fluid from being cooled by the room temperature main body cover. Therefore, the present invention can reduce the heat loss of the working fluid.

  In the present invention, configurations (a) to (e) can be preferably employed.

(A) An inlet-side seal member that seals the inlet-side gap is provided, and the inlet-side seal member is a heat insulating material.

  According to the configuration (a), the gas inside the main body cover acts as a heat insulating layer that blocks the orbiting scroll and the fixed scroll from the outside of the scroll expander. That is, heat dissipation from the fixed scroll is prevented. Also, the working fluid vapor inside the body cover keeps the fixed scroll warm. Therefore, the present invention can further reduce the heat loss of the working fluid.

(B) The main body cover is fixed to the fixed scroll via a cover spacer, and the cover spacer is a heat insulating material.

  According to the configuration (b), it is possible to prevent heat from escaping from the fixed scroll to the main body cover. Therefore, the present invention can further reduce the heat loss of the working fluid.

(C) In a central axis direction parallel to the central axis, the pin is fixed to the main body cover via the fixed scroll so that the fixed scroll does not fall off the main body cover without being fixed to the main body cover. And / or a long hole which enables each pin to move to the above-mentioned radial direction is formed in the body cover.

  According to the configuration (c), the fixed scroll and the main body cover are not always in contact with each other, so that heat is hardly conducted from the fixed scroll to the main body cover. Further, since the pin is movable in the radial direction, it is prevented that the fixed scroll and the main body cover are fixed in contact with each other. Therefore, the present invention can further reduce the heat loss of the working fluid.

(D) an outlet member having a working fluid passage extending from the outlet on the inside of the main body cover to the outer side of the main body cover, so that the main body cover and the outlet member are not in contact with each other; An outlet-side gap is formed between them, an outlet-side seal member that seals the outlet-side gap is provided, and the outlet-side seal member is a heat insulating material.

  According to the configuration (d), the outlet member in contact with the working fluid and the main body cover are thermally blocked. As a result, it is possible to prevent the high temperature working fluid from being cooled by the room temperature main body cover. Therefore, the present invention can further reduce the heat loss of the working fluid.

(E) The orbiting scroll includes a connecting portion that connects the first portion that forms the expansion chamber together with the fixed scroll and the second portion that supports the crank, and the connecting portion in the extending direction of the connecting portion. A thinned portion or a thin portion is formed in a part of the cross section.

  According to the configuration (e), the amount of heat escaping from the expansion chamber side formed by the swing scroll and the fixed scroll to the crank is reduced. Therefore, the present invention can further reduce the heat loss of the working fluid.

It is sectional drawing of a scroll type expander. It is the figure which looked at the rocking scroll from the central axis direction. It is sectional drawing of the scroll type expander which shows the periphery of a premixing chamber. It is the figure which looked at the fixed side and the back side fixed scroll from the front side. It is the figure which looked at the heat insulation packing from the front side. It is sectional drawing of the scroll type expander which shows the periphery of a discharge part. It is sectional drawing of the connection part in the direction where a connection part is extended. It is the figure which looked at the fixed side and the back side fixed scroll from the front side (2nd Embodiment). It is sectional drawing which shows the attachment seat of a fixed side cover, and the attachment flange of a fixed scroll (2nd Embodiment). It is the figure which looked at the circumference of a connecting part from the direction of a central axis (3rd embodiment). It is sectional drawing of the connection part in the direction where a connection part is extended (3rd Embodiment).

(First embodiment)
FIG. 1 is a cross-sectional view of a scroll type expander. The scroll type expander includes a swing scroll 1, a front fixed scroll 2, a rear fixed scroll 3, a front cover 4, a rear cover 5, two cranks 6, two premixing chambers 7, and two outlet members. 8 is provided.

  In the drawings, AC, DC, DL, and PC indicate axes or directions. AC indicates a central axis of swinging of the swing scroll 1 with respect to the fixed scrolls 2 and 3. DC indicates a direction parallel to the central axis AC (hereinafter referred to as the central axis direction). DL indicates the longitudinal direction of the orbiting scroll 1. PC indicates a rocking surface (rotating surface) of the rocking scroll 1 with respect to the fixed scrolls 2 and 3. The central axis direction DC is perpendicular to the swing surface PC. The longitudinal direction DL is perpendicular to the central axis direction DC and is a direction in which the two cranks 6 and 6 are arranged.

  FIG. 2 is a view of the orbiting scroll 1 as viewed from the central axis direction DC. The orbiting scroll 1 includes an end plate 10, a scroll wall 11, and two bearings 12.

  The end plate 10 is a plate-like member that extends along the rocking surface PC and extends along the longitudinal direction DL. The end plate 10 includes a scroll support portion 101, two crank support portions 102, and two connection portions 103. The scroll support portion 101 is in the center, and the two crank support portions 102 are on both sides of the scroll support portion 101. The connecting portion 103 connects the scroll support portion 101 and the crank support portion 102.

  The scroll wall 11 is a wall perpendicular to the swing surface PC, and the shape of this wall is a scroll shape. The scroll wall 11 is fixed to the scroll support portion 101.

  The bearing 12 is fitted into a through hole formed in the crank support portion 102. The inside of the crank support portion 102 is penetrated along the central axis direction DC. The bearing 12 is a ball bearing and has an inner ring 121 and an outer ring 122. An inner ring spacer 13 is fitted into the inner ring 121 of the bearing 12.

  In FIG. 1, the fixed scroll 2 includes an end plate 20 and a scroll wall 21. The end plate 20 of the fixed scroll 2 corresponds to the end plate 10 of the swing scroll 1. The end plate 20 is a plate-like member that extends along a plane parallel to the swing surface PC. The scroll wall 21 corresponds to the scroll wall 11 of the swing scroll 1. The scroll wall 21 has a wall perpendicular to the swing surface PC, and the shape of the wall is a scroll shape. The scroll wall 21 is fixed to the end plate 20.

  The end plate 20 is penetrated along the central axis direction DC at the center and the end. A through hole formed in the center is a working fluid supply port 20a. A through hole formed in the end is a working fluid discharge port 20b. The supply port 20a is located on the central axis AC.

  In FIG. 2, the supply port 20 a is located at the center of the scroll walls 11 and 21. The discharge port 20 b is located at the outer end of the scroll walls 11 and 21. In FIG. 2, the scroll wall 21 is not shown, but the scroll wall 21 is at a position close to the scroll wall 11.

  A plurality of expansion chambers are formed between the orbiting scroll 1 and the fixed scroll 2. The plurality of expansion chambers are formed between the scroll walls 11 and 21 when viewed from the central axis direction DL. Here, the orbiting scroll 1 can be swung relative to the fixed scroll 2, but the scroll walls 11 and 21 are constantly in contact. For this reason, the space in the scroll walls 11 and 21 is divided by the wall surfaces of the scroll walls 11 and 21. As a result, each expansion chamber has a crescent shape. Similarly, a plurality of expansion chambers are formed between the swing scroll 1 and the fixed scroll 3.

  The fixed scroll 2 and the fixed scroll 3 have the same configuration. The end plate 20, the supply port 20a, the discharge port 20b, and the scroll wall 21 in the fixed scroll 2 correspond to the end plate 30, the supply port 30a, the discharge port 30b, and the scroll wall 31 in the fixed scroll 3, respectively.

  In FIG. 2, the two cranks 6 are arranged outside the fixed scroll 2 in the radial direction of the central axis AC. That is, the drive system in the scroll type expander of this embodiment is an outer periphery drive type.

  In FIG. 1, the crank 6 includes two crankshafts 61 and an eccentric shaft 62. The two crankshafts 61 and the eccentric shaft 62 are integrally formed, and the eccentric shaft 62 is fixed to the crankshaft 61. The eccentric shaft 62 is disposed between the two crankshafts 61. The center axis A61 of the crankshaft 61 and the center axis A62 of the eccentric shaft 62 are different. For this reason, when the crankshaft 61 rotates, the eccentric shaft 62 revolves around the crankshaft 61.

  The eccentric shaft 62 includes two shaft portions 621, two link portions 622, and a fitting portion 623. The two link portions 622 are disposed at both ends of the eccentric shaft 62. The fitting portion 623 is disposed at the center of the eccentric shaft 62. The shaft portion 621 is disposed between the link portion 622 and the fitting portion 623. The shaft portion 621 is a columnar shaft member. The link part 622 is a columnar member having an outer diameter larger than that of the shaft part 621. In the link part 622, the crankshaft 61 and the eccentric shaft 62 are connected. The fitting portion 623 is disposed in the inner ring spacer 13 of the orbiting scroll 1.

  A balance weight 15 is fixed to the inner ring spacer 13 of the swing scroll 1. Here, when the swing scroll 1 swings, the position of the center of gravity of the swing scroll 1 changes. The balance weight 15 is provided in order to cancel the generation of a load due to a change in the center of gravity position of the orbiting scroll 1.

  In FIG. 1, two bearings 9 are arranged for each crank 6. One bearing 9 is supported by the front cover 4 and rotatably supports the front crankshaft 61. The other bearing 9 is supported by the back side cover 5 and rotatably supports the back side crankshaft 61. The scroll type expander includes four bearings 9 as a whole. The bearing 9 is a ball bearing and includes an inner ring 91 and an outer ring 92.

  In FIG. 1, the right side of the figure is the front side of the scroll type expander, and the left side of the figure is the back side of the scroll type expander. A belt 16 is provided on the back side in order to synchronize the rotation of the two crankshafts 61. A pulley 17 is fixed to the crankshaft 61 on the back side of the bearing 9. The belt 16 is wound around two pulleys 17.

  The operation of the scroll expander will be schematically described. The working fluid is supplied from supply ports 20a and 30a to an expansion chamber formed between the orbiting scroll 1 and the fixed scrolls 2 and 3, and is discharged from the discharge ports 20b and 30b of the fixed scrolls 2 and 3. . The working fluid expands the expansion chamber while traveling between the swing scroll 1 and the fixed scrolls 2 and 3. As a result, a part of the pressure of the working fluid is lost, and the swing scroll 1 swings with respect to the fixed scrolls 2 and 3. That is, the scroll type expander obtains power for driving the two cranks 6 and 6 by the pressure loss of the working fluid.

  Next, the configuration of each part of the scroll expander will be described in detail.

  In FIG. 1, the shape of the front side cover 4 is a dish shape. The front side cover 4 is formed with an inlet opening H41, two bearing openings H42, and an outlet opening H43. The inlet opening H41 corresponds to the supply port 20a. The inlet opening H41 and the supply port 20a are on the same axis parallel to the central axis AC. The bearing opening H42 corresponds to the bearing 9 that supports the crank 6. The bearing opening H42 and the output shaft (crankshaft 61) of the crank 6 are on the same axis parallel to the central axis AC. The outlet opening H43 corresponds to the discharge port 20b. The outlet opening H43 and the outlet 20b are on the same axis parallel to the central axis AC.

  The shape of the back side cover 5 is a bowl shape. The back cover 5 also has the same structure as the front cover 4 with respect to the opening. In other words, the back cover 5 is formed with an inlet opening H51, two bearing openings H52, and an outlet opening H53. The inlet opening H51, the two bearing openings H52, and the outlet opening H53 correspond to the inlet opening H41, the two bearing openings H42, and the outlet opening H43, respectively.

  The front side cover 4 and the back side cover 5 constitute a main body cover of the scroll type expander. The main body cover includes the orbiting scroll 1 and the two scrolls 1 except for the supply ports 20a and 30a and the discharge ports 20b and 30b formed in the fixed scrolls 2 and 3 and the output shaft (crankshaft 61) of the crank 6. The entire fixed scrolls 2 and 3 and the two cranks 6 are covered.

  In FIG. 1, two premixing chambers 7 are arranged on the central axis AC. The supply ports 20a and 30a are also on the central axis AC. For this reason, the premixing chamber 7 and the supply port 20a (or 30a) are coaxially arranged on the front side and the back side.

  FIG. 3 is a sectional view of the scroll expander showing the periphery of the premixing chamber 7. The premixing chamber (inlet member) 7 includes a first inlet block 71 and a second inlet block 72. The first inlet block 71 and the second inlet block 72 are fixed to the end plate 20 of the fixed scroll 2 together.

  The premixing chamber 7 is formed with a passage through which the working fluid passes from the outside of the body cover (4, 5) to the inside supply port 20a. The passage includes a pipe connection portion 711, a hemispherical portion 712, a first tapered portion 721, a cylindrical portion 722, and a second tapered portion 723. The pipe connection portion 711 and the hemispherical portion 712 are formed on the inner surface of the first inlet block 71. The first tapered portion 721, the cylindrical portion 722, and the second tapered portion 723 are formed on the inner surface of the second inlet block 72.

  The premixing chamber 7 is a chamber for mixing the working fluid and the sealing agent. For this reason, the premixing chamber 7 includes a sealing agent chamber 724 for storing the sealing agent, and a sealing agent supply pipe 725 for supplying the sealing agent to the working fluid. The sealant chamber 724 is a groove formed on the outer surface of the second inlet block 72. The sealant supply pipe 725 is formed by penetrating the inner surface and the outer surface of the second inlet block 72.

  The working fluid is, for example, steam. The sealing agent is, for example, water or oil. The sealing agent is used to seal the expansion chamber. The gap between the screen walls 11 and 21 and the gap between the screen wall 21 and the end plate 10 are sealed by the sealing agent.

  The working fluid passage is connected to the supply port 20 a of the fixed scroll 2. That is, the 2nd taper part 723 and the supply port 20a are connecting. On the other hand, a passage for the sealing agent is formed from the sealing agent chamber 724 to the cylindrical portion 722. For this reason, the working fluid and the sealing agent are mixed in the premixing chamber 7. The mixed working fluid and sealing agent are supplied into the supply port 20a.

  The front-side premixing chamber 7 is disposed in the inlet opening H41. The inner surface 41a of the inlet opening H41 and the outer surface 71a of the first inlet block 71 are cylindrical outer surfaces around the central axis AC. The outer surface 71a is opposed to the inner surface 41a.

  An entrance-side gap L1 is formed between the outer surface 71a and the inner surface 41a. For this reason, the premixing chamber 7 and the front side cover 4 are not in contact.

  An O-ring (inlet side seal member) 18 is disposed between the outer surface 71a and the inner surface 41a. The O-ring 18 is fitted in a groove formed in the outer surface 71a. The O-ring 18 seals the entrance-side gap L1 between the outer surface 71a and the inner surface 41a.

  The O-ring 18 is made using a material having lower thermal conductivity than the material of the first inlet block 71 and the front side cover 4. For example, the material of the first inlet block 71 and the front side cover 4 is metal, and the material of the O-ring 18 is resin. For this reason, the O-ring 18 is a heat insulating material.

  Similarly to the front-side premixing chamber 7, the back-side premixing chamber 7 is also disposed in the inlet opening H 51 of the back cover 5. The inner surface 51a of the inlet opening H51 corresponds to the inner surface 41a of the inlet opening H41. A gap is formed between the outer surface 71 a and the inner surface 51 a of the first inlet block 71. An O-ring 18 is disposed between the outer surface 71a and the inner surface 51a.

  Next, a fixing structure between the fixed scrolls 2 and 3 and the back side cover 5 will be described. In FIG. 1, the back cover 5 includes a bowl-shaped cover body 50 and a mounting seat 55. The attachment seat 55 is a member for attaching the fixed scrolls 2 and 3 to the cover main body 50. The mounting seat 55 extends from the cover body 50 to the front side.

  In FIG. 3, the fixed scroll 2 includes a mounting flange 22 in addition to the end plate 20 and the scroll wall 21. The mounting flange 22 extends outside the scroll wall 21 along the swing surface PC. The fixed scroll 3 is also provided with a mounting flange 32. The head of the bolt 19, the mounting flange 22, the mounting flange 32, the heat insulating packing (cover spacer) 24, and the mounting seat 55 are arranged from the front side to the back side. The mounting flanges 22 and 32 and the mounting seat 55 are fixed by the same bolt 19 via the heat insulating packing 24. As a result, the fixed scrolls 2 and 3 are fixed to the back side cover 5.

  A gap L2 is provided between the mounting flange 23 and the mounting seat 55 in the central axis direction DC. However, the gap L <b> 2 is filled with the heat insulating packing 24.

  The heat insulating packing 24 is made using a material having a lower thermal conductivity than the material of the mounting seat 55 (back side cover 5) and the mounting flanges 22, 23 (fixed scrolls 2, 3). For example, the back cover 5 and the fixed scrolls 2 and 3 are made of metal, and the heat insulating packing 24 is made of resin. For this reason, the heat insulating packing 24 is a heat insulating material.

  FIG. 4 is a view of the front side and rear side fixed scrolls 2 and 3 as seen from the front side. The mounting flanges 22 and 22 (32 and 32) are disposed on both sides of the end plate 20 (30) in a direction perpendicular to the longitudinal direction DL and the central axis direction DC (direction perpendicular to the paper surface of FIG. 1). . When viewed from the central axis direction DC, the mounting flanges 22 and 32 have an arc shape. In the radial direction of the central axis AC, the mounting flanges 22 and 32 are outside the end plate 10 of the orbiting scroll 1. For this reason, the interference between the mounting flanges 22 and 32 and the end plate 10 is prevented.

  In FIG. 4, bolts 29 are provided to fix the mounting flanges 22 and 32. The bolt 29 fixes the mounting flanges 22 and 32.

  FIG. 5 is a view of the heat insulating packing 24 as viewed from the front side. The shape of the heat insulating packing 24 is an arc shape when viewed from the central axis direction DC. The shape of the mounting seat 55 of the back side cover 5 is also an arc shape (not shown) as seen from the central axis direction DC. The heat insulating packing 24 is formed thin except for the bolt insertion portion. The heat insulating packing 24 is narrower than the front surface 55a (FIG. 3) of the mounting seat 55 and the mounting flange 22 in the area of the axial cross section of the central axis AC. For this reason, the contact area of the heat insulating packing 24, the mounting seat 55, and the mounting flange 22 is reduced.

  The structure of the outlet member 8 will be described with reference to FIG. FIG. 6 is a cross-sectional view of the scroll expander showing the periphery of the outlet member 8. Here, the cut surface of FIG. 6 is parallel to the cut surface of FIG. 1, but is not the same. For this reason, the shapes of the scrolls 1, 2 and 3 and the covers 4 and 5 are different between FIGS. 1 and 6.

  In FIG. 6, the outlet member 8 is disposed on an axis parallel to the central axis AC. The outlet 20 a is also on the same axis as the outlet member 8. For this reason, the outlet member 8 and the discharge port 20b are coaxially arranged on the front side and the back side. Hereinafter, the outlet member 8 on the front side will be described. The outlet member 8 on the back side also has the same configuration as the outlet member 8 on the front side.

  The outlet member 8 includes an outlet block 81 and a discharge pipe 82. The discharge pipe 82 is a cylinder. The discharge pipe 82 is inserted into the outlet block 81 and fixed to the outlet block 81.

  The discharge pipe 82 is inserted into the outlet opening H43. The outlet opening H43 is a cylindrical portion that protrudes to the back side of the front cover 4. The inner surface 43a of the outlet opening H43 faces the outer surface 82a of the discharge pipe 82 in the radial direction of the central axis DC.

  Between the inner surface 43a of the outlet opening H43 and the outer surface 82a of the discharge pipe 82, an outlet-side radial clearance L3 is formed. For this reason, the discharge pipe 82 and the front side cover 4 are not in contact.

  Between the end surface 81a of the outlet block 81 and the end surface 43b of the outlet opening H43, an outlet-side axial gap L4 is provided. However, the outlet-side axial gap L4 is filled with the heat insulating packing 25.

  The heat insulating packing 25 completely seals the outlet side axial gap L4. For this reason, the heat insulating packing 25 is an outlet side seal member that seals the outlet side axial gap L4 (outlet side gap).

  The heat insulating packing 25 is made using a material having lower thermal conductivity than the material of the outlet block 81 (outlet member 8) and the front side cover 4 (main body cover). For example, the material of the outlet block 81 and the front cover 4 is metal, and the material of the heat insulating packing 25 is resin. For this reason, the heat insulating packing 25 is a heat insulating material.

  The outlet member 8 is formed with a passage through which the working fluid passes from the discharge port 20b to the outside of the main body cover. The passage includes an inner surface 82 a of the discharge pipe 82, a first pipe connection part 811, and a second pipe connection part 812. The first pipe connection portion 811 and the second pipe connection portion 812 form the inner surface of the outlet block 81 and penetrate the outlet block 81. A pipe 14 is inserted into the first pipe connecting portion 811 from the outside of the screen expander, and the pipe 14 is fixed to the outlet block 81.

  An end portion on the back side of the discharge pipe 82 is inserted into the second pipe connection portion 812. The outer surface 82a of the discharge pipe 82 faces the second pipe connection portion 812 and is substantially in contact therewith.

  An O-ring 26 is disposed between the outer surface 82a and the second pipe connection portion 812. The O-ring 25 is fitted in a groove formed in the second pipe connection portion 812. The O-ring 26 seals the gap between the outer surface 82a and the second pipe connection portion 812.

  An end of the discharge pipe 82 on the discharge port 20 b side is inserted into the support portion 201 of the end plate 20. The support part 201 is a cylindrical part which protrudes from the periphery of the discharge port 20b to the back side in the end plate 20. The outer surface 82a of the discharge pipe 82 is opposed to and substantially in contact with the inner surface 201a of the support portion 201.

  An O-ring 27 is disposed between the outer surface 82a and the inner surface 201a. The O-ring 27 is fitted in a groove formed on the outer surface 82a. The O-ring 27 seals the gap between the outer surface 82a and the inner surface 201a.

  With reference to FIGS. 2 and 7, the structure of the connecting portion 103 of the orbiting scroll 1 will be described. In FIG. 2, the scroll support portion 101 of the end plate 10 and the scroll wall 11 are a first portion that forms an expansion chamber together with the fixed scrolls 2 and 3. The crank support portion 102 of the end plate 10 is a second portion that supports the crank 6. The connecting part 103 of the end plate 10 connects the first part and the second part. The connecting portion 103 is a recessed portion in the end plate 10.

  FIG. 7 is a cross-sectional view of the connecting portion 103 in the direction in which the connecting portion 103 extends (longitudinal direction DL). In FIG. 7, the cross-sectional shape of the connection part 103 is H-shaped. The connecting portion 103 is formed with a thick portion 103a and a thin portion 103b. The thick part 103a and the thin part 103b are two parts having different thicknesses in the central axis direction DC. The H-shaped vertical axis is composed of two thick portions 103a. The H-shaped horizontal axis is constituted by a thin portion 103b.

  The operation of the first embodiment will be described in detail with reference to FIG.

  A high-pressure working fluid is supplied to the two premixing chambers 7 through a pipe connected to the premixing chamber 7 from the outside of the scroll expander. In the premixing chamber 7, the working fluid and the sealing agent are mixed. On the front side, the mixed working fluid is supplied into the swing scroll 1 and the fixed scrolls 2 and 3 through the supply port 20a. As the working fluid travels between the scroll walls 11, 21 (and 31), the plurality of expansion chambers formed between the scroll walls 11, 21 (and 31) are expanded. At this time, instead of the working fluid losing pressure due to expansion, the orbiting scroll 1 is driven. By driving the orbiting scroll 1, the two cranks 6 are driven. As a result, rotational power is output from the two crankshafts 61. The working fluid whose pressure has decreased is discharged from the discharge port 20b to the outlet member 8. Further, the working fluid is discharged to the outside of the scroll expander through the pipe 14 connected to the outlet member 8.

  The high-pressure and high-temperature working fluid passes through the premixing chamber 7, the rocking scroll 1 and the fixed scroll 2 (and 3), and the outlet member 8. Here, high temperature means temperature higher than normal temperature. Therefore, the premixing chamber 7 (the first inlet block 71 and the second inlet block 72), the orbiting scroll 1, the fixed scroll 2 (and 3), and the outlet member 8 (the outlet block 81 and the discharge pipe 82) are operated. Heated by the fluid.

  A part of the working fluid leaks from between the rocking scroll 1 and the fixed scroll 2. The leaked working fluid evaporates. The working fluid vapor fills the inside of the main body cover (the front side cover 4 and the back side cover 5).

  The first embodiment has the following operations and effects by the following configuration.

  In FIG. 1, the main body cover (the front side cover 4 and the back side cover 5) is not in contact with the swing scroll 1 and the fixed scrolls 2 and 3. The two inlet members are in contact with the fixed scrolls 2 and 3, respectively. Further, an inlet-side gap L1 is formed between the main body cover and the inlet member (the first inlet block 71 and the second inlet block 72).

  For this reason, the inlet member which a working fluid contacts and the main body cover are interrupted | blocked thermally. As a result, it is possible to prevent the high temperature working fluid from being cooled by the room temperature main body cover. Therefore, the first embodiment can reduce the heat loss of the working fluid.

  In FIG. 3, an O-ring 18 that seals the inlet-side gap L1 is provided. The O-ring 18 is a heat insulating material. For this reason, the inside of a main body cover is sealed with respect to the exterior of a main body cover. Inside the main body cover, there are air and vapor of working fluid leaking into the main body cover. The gas inside the main body cover cannot escape to the outside of the main body cover. Further, the thermal insulation between the inlet member and the main body cover is maintained.

  The gas inside the main body cover acts as a heat insulating layer that blocks the orbiting scroll 1 and the fixed scrolls 2 and 3 from the outside of the scroll expander. That is, heat radiation from the fixed scrolls 2 and 3 is prevented. Also, the working fluid vapor inside the main body cover keeps the fixed scrolls 2 and 3 warm. Therefore, the first embodiment can further reduce the heat loss of the working fluid.

  In FIG. 3, the back side cover 5 (main body cover) is fixed to the fixed scrolls 2 and 3 via a heat insulating packing 24 (cover spacer).

  This prevents heat from escaping from the fixed scrolls 2 and 3 to the back cover 5 (main body cover). Therefore, the first embodiment can further reduce the heat loss of the working fluid.

  In FIG. 6, an outlet side axial clearance L4 (exit side gap) is formed between the outlet block 81 (outlet member 8) and the front side cover 4 (main body cover). A heat insulating packing 27 is disposed in the outlet side axial gap L4. The heat insulating packing 27 is a heat insulating material.

  For this reason, the outlet member which the working fluid contacts and the main body cover are thermally blocked. As a result, it is possible to prevent the high temperature working fluid from being cooled by the room temperature main body cover. Therefore, the first embodiment can further reduce the heat loss of the working fluid.

  In FIG. 7, a thin-walled portion 103b that is thinner than the thick-walled portion 103a is formed in a part of the cross-section of the connecting portion 103. That is, the heat transfer area in the connecting portion 103 is reduced.

  For this reason, the amount of heat that escapes from the expansion chamber side formed by the orbiting scroll 1 and the fixed scrolls 2 and 3 to the crank 6 is reduced. Therefore, the first embodiment can further reduce the heat loss of the working fluid.

(Other embodiments)
Next, another embodiment will be described.

  The second embodiment is another embodiment relating to a fixing structure between the fixed scrolls 2 and 3 and the back side cover 5. The difference between the second embodiment and the first embodiment is only the fixing structure. Therefore, only the fixing structure will be described below.

  FIG. 8 is a view of the fixed-side and back-side fixed scrolls 2 and 3 as viewed from the front side. The fixing structure of the second embodiment is different from the fixing structure of the first embodiment in the following three points. A stepped bolt 219 is used instead of the bolt 19 of the first embodiment. In order to insert the stepped bolt 219, long holes 222 and 232 are formed in the mounting flanges 22 and 32 instead of the circular holes of the first embodiment. The heat insulating packing 24 of the first embodiment is not arranged between the mounting seat 55 of the back side cover 5 and the mounting flange 22.

  In FIG. 8, the long hole 222 is formed in the radial direction of the central axis DC. For this reason, the mounting flange 22 can move with respect to the mounting seat 55 within the range of the formation length of the long hole 222.

  FIG. 9 is a cross-sectional view showing the mounting seat 55 of the fixed side cover 5 and the mounting flanges 22 and 32 of the fixed scrolls 2 and 3. In FIG. 9, the stepped bolt 219 has a cylindrical portion 219a and a screw portion 219b. The cylindrical portion 219a has a larger diameter than the screw portion 219b. The axial length L219 of the cylindrical portion 219a is longer than the thickness L5 of the mounting flanges 22 and 32 combined. Here, the thickness L5 is a length in the central axis direction DC. For this reason, the mounting flanges 22 and 32 can move within the range of the difference between the thickness L5 and the length L219 in the axial direction of the stepped bolt 219.

  The second embodiment has the following operations and effects by the following configuration.

  The fixed scrolls 2 and 3 are not fixed to the main body cover (mounting seat 55) by the stepped bolts 219 (pins) and do not fall off from the main body cover (mounting seat 55). Further, the stepped bolt 219 can move in the radial direction with respect to the mounting flanges 22 and 32 through the long holes 222 and 232. That is, even if the fixed scrolls 2 and 3 are thermally expanded, the fixed scrolls 2 and 3 are prevented from being fixed to the main body cover (mounting seat 55).

  Since the fixed scrolls 2 and 3 are not always in contact with the main body cover, heat is hardly conducted from the fixed scrolls 2 and 3 to the main body cover. Further, since the stepped bolt 219 (pin) is movable in the radial direction, it is prevented that the fixed scrolls 2 and 3 are fixed in contact with the main body cover. Therefore, the second embodiment can further reduce the heat loss of the working fluid.

  3rd Embodiment is other embodiment regarding the connection part 103 of 1st Embodiment. In 3rd Embodiment, it replaces with the connection part 103 of 1st Embodiment, and the connection part 303 is used. Accordingly, only the connecting portion 303 will be described below.

  FIG. 10 is a view of the periphery of the connecting portion 303 as seen from the central axis direction DC. In FIG. 10, the connecting portion 303 is formed with a lightening hole 303a. The lightening hole 303a penetrates the connecting portion 303 along the central axis direction DC.

  FIG. 11 is a cross-sectional view of the connecting portion 303 in the direction in which the connecting portion 303 extends (longitudinal direction DL). In FIG. 11, the cross-sectional shape of the connecting portion 303 is two I-shapes arranged in parallel.

  The third embodiment has the same operations and effects as the connecting portion 103 in the first embodiment.

DESCRIPTION OF SYMBOLS 1 Swing scroll 2 Front side fixed scroll 3 Back side fixed scroll 4 Front side cover (a part of main body cover)
5 Back cover (part of main unit cover)
6 Crank 7 Premixing chamber (inlet member)
8 Outlet member 9 Bearing 10 End plate 18 O-ring (Inlet side seal member)
24 Insulation packing (cover spacer)
25 Insulation packing (Outlet side seal member)
219 Stepped bolt (pin)
L1 Inlet side clearance 20a, 30a Supply port 20b, 30b Discharge port 61 Crankshaft (Crank output shaft)
101 Scroll support (part of the first part)
102 Crank support (second part)
103, 303 connecting part 103b thin part (thin part)
303a Meat removal hole (part of meat removal)
322, 332 Long hole AC center axis DC center axis direction PC rocking surface DL longitudinal direction L1 inlet side gap L2 gap L3 outlet side radial gap (outlet side gap)
L4 Outlet side axial clearance (exit side clearance)

Claims (6)

A fixed scroll is disposed on each side of the swing scroll on the center axis of the swing scroll with respect to the fixed scroll, and a plurality of cranks for driving the swing scroll are disposed outside the fixed scroll in the radial direction of the center axis. And a scroll-type fluid machine of an outer peripheral drive type in which a supply port of a working fluid formed in the fixed scroll is disposed on the central axis,
Except for the supply port, the working fluid discharge port formed in the fixed scroll, and the output shaft of the crank, the swing scroll, the two fixed scrolls, and the plurality of cranks are covered, and the swing scroll and the two A main body cover disposed away from the fixed scroll;
An inlet member having a passage of working fluid from a supply port inside the body cover to the outside of the body cover;
With
An inlet-side gap is formed between the main body cover and the inlet member so that the main body cover and the inlet member do not contact each other.
Scroll type expander. An inlet-side seal member that seals the inlet-side gap is provided, and the inlet-side seal member is a heat insulating material.
The scroll type expander according to claim 1. The body cover is fixed to the fixed scroll via the cover spacer, and the cover spacer is a heat insulating material.
The scroll type expander according to claim 1 or 2. In the central axis direction parallel to the central axis, the pin is fixed to the main body cover via the fixed scroll so that the fixed scroll does not fall off the main body cover without being fixed to the main body cover,
In the fixed scroll and / or the main body cover, a long hole is formed so that each pin can be moved in the radial direction.
The scroll type expander as described in any one of Claims 1-3. An outlet member having a passage of working fluid from a discharge port inside the body cover to the outside of the body cover;
An outlet-side gap is formed between the main body cover and the outlet member so that the main body cover and the outlet member do not contact each other,
An outlet side sealing member that seals the outlet side gap is provided, and the outlet side sealing member is a heat insulating material,
The scroll type expander as described in any one of Claims 1-4. The orbiting scroll includes a connecting portion that connects a first portion that forms an expansion chamber together with the fixed scroll, and a second portion that supports the crank,
In a part of the cross-section of the connecting portion in the extending direction of the connecting portion, a portion with a lightening or a thin portion is formed,
The scroll type expander as described in any one of Claims 1-5.

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