JP6769201B2 - Scroll fluid machine - Google Patents

Description

The present invention relates to a scroll fluid machine .

Conventionally, in a scroll fluid machine provided with a fixed scroll and a swivel scroll, a configuration is known in which a groove is provided at the tip of an outer peripheral wrap provided on the fixed scroll and a seal member is arranged in the groove to close a gap with the swivel scroll. .. Patent Document 1 discloses, for example, a scroll fluid machine of this type. Patent Document 1 describes a scroll fluid machine in which a double-row external seal is provided at the tip of a fixed scroll outer peripheral wrap.

JP-A-2015-124739

As in Patent Document 1, by arranging the sealing member at the tip of the outer peripheral wrap, the gap between the outer peripheral wrap and the substrate portion of the swivel scroll can be filled, but the fluid to be expanded (for example, steam) is grooved. A force may be applied to push the seal member toward the swivel scroll side by wrapping around to the back side of the seal member through the gap. The sealing member that receives the pressure of the fluid wears faster than usual, which causes the fluid to leak to the outside and to accelerate the replacement period. There was room for improvement in the conventional seal structure from the viewpoint of preventing abnormal wear of the seal member.

An object of the present invention is to provide a scroll fluid machine capable of avoiding a situation in which the tip of the sealing member is abnormally worn due to fluid (for example, steam) wrapping around the back side of the sealing member arranged at the tip of the outer peripheral wrap. And.

The present invention is a scroll fluid machine using steam as a working fluid, in which a swirling scroll provided with a spiral swirling lap on the plate surface of the swirling side substrate portion and the swirling lap meshing with the swirling lap on the plate surface of the fixed side substrate portion. A fixed scroll provided with a spiral fixed wrap and a tubular outer wrap surrounding the fixed wrap, and a seal member arranged along the circumferential direction in a concave accommodating portion provided at the tip of the outer wrap. The seal member is contained in a first seal portion that contacts the swivel side substrate portion in a state of being accommodated in the accommodating portion and fills a gap between the swivel side substrate portion and the outer peripheral wrap, and inside the accommodating portion . The present invention relates to a scroll fluid machine having a second seal portion that fills a gap between the inner peripheral side of the first seal portion and the accommodating portion in a non-contact state with the swivel side substrate portion .

It is preferable that the seal member is further provided with an urging member that is arranged in the accommodating portion and biases only the first seal portion to the swivel side substrate portion.

The second seal portion is an O-ring, and it is preferable that the inner wall on the inner peripheral side of the accommodating portion is provided with a fitting groove into which the second seal portion is fitted.

Further, the first seal portion and the second seal portion may be integrally molded products.

According to the scroll fluid machine of the present invention, it is possible to avoid a situation in which the tip of the seal member is abnormally worn due to fluid (for example, steam) wrapping around the back side of the seal member arranged at the tip of the outer peripheral wrap.

It is the schematic of the steam utilization system which uses the scroll fluid machine (scroll expansion machine) which concerns on one Embodiment of this invention. It is a front view which shows an example of the arrangement of the scroll expander of this embodiment, and the steam pipe connected to the scroll expander. It is a vertical sectional view of the scroll expander of this embodiment. It is an enlarged sectional view which shows the steam seal member of this embodiment and its vicinity. It is an enlarged sectional view which shows the steam seal member of the 1st modification and its vicinity. It is an enlarged sectional view which shows the steam seal member of the 2nd modification and the vicinity thereof. It is a figure which shows typically the arrangement of the crankshaft and the ventilation structure of this embodiment.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

<System configuration>
FIG. 1 is a schematic view of a steam utilization system 1 in which a scroll fluid machine (scroll expander) according to an embodiment of the present invention is used. The steam utilization system 1 of the present embodiment is also an air compression device that extracts a driving force from steam and performs air compression using the driving force.

As shown in FIG. 1, the steam utilization system 1 of the present embodiment is supplied from a steam generator 2 that supplies steam, a scroll expander 3 that is operated by steam supplied from the steam generator, and a scroll expander 3. A compressor 4 that is driven by the driving force to be generated and discharges compressed air, a blower 7, and a control device 5 that performs various controls are provided as a main configuration.

The steam generator 2 includes a steam boiler 11 and a steam header 12 to which steam is sent from the steam boiler 11. The steam boiler 11 heats water supplied from a water pipe, a groundwater source, or the like to generate steam. In the steam header 12, a condensate treatment agent is added from the condensate treatment agent addition device 13 in order to prevent corrosion of the pipe (steam / condensate pipe) caused by condensed water of steam. In the present embodiment, the condensate treatment agent is added to the steam header 12, but it is added to the boiler water supply to protect both the boiler can body and the steam / condensate pipe with the condensate treatment agent. May be good.

The scroll expander 3 is a prime mover that expands the steam supplied from the steam header 12 through the steam supply pipe 15 to extract the driving force. The steam whose driving force is extracted by the scroll expander 3 is sent to a steam header (not shown) for recovery. Since the scroll expander 3 also functions as a pressure reducing valve, the steam after depressurization (after expansion) sent to the above-mentioned recovery steam header can be used as it is as low pressure steam in various steam-using devices. ..

The compressor 4 is a driven machine driven by a driving force transmitted from the scroll expander 3 through the transmission mechanism 6, and is a scroll type fluid machine having substantially the same structure as the scroll expander 3.

The blower 7 is an air supply source of a ventilation device that sends cooling air to the scroll expander 3 via the air supply duct 240. The air (cooling air) that has cooled the scroll expander 3 is discharged to the outside through the exhaust duct 250. An air supply temperature sensor 241 for detecting the supply air temperature is arranged in the air supply duct 240, and an exhaust temperature sensor 251 for detecting the exhaust temperature is arranged in the exhaust duct 250.

The control device 5 is a computer that controls various types of the steam utilization system 1, and is electrically connected to various sensors, an on-off valve 17, and the like.

<Steam supply path and discharge path>
FIG. 2 is a front view showing an example of a steam pipe and a ventilation structure connected to the scroll expander 3 and the scroll expander 3 of the present embodiment. FIG. 3 is a vertical cross-sectional view of the scroll expander 3 of the present embodiment. The scroll expander 3 shown in FIG. 2 is a vertical scroll expander 3 in which the turning axis faces in the horizontal direction. In the following description, the thickness direction of the scroll expander 3 and the direction parallel to the horizontal direction of the crankshaft 70 may be described as the "axial direction".

<Steam supply pipe>
The steam supply pipe 15 for supplying steam to the scroll expander 3 will be described. The steam supply pipe 15 is a pipe that supplies steam to the scroll expander 3 sent from the steam header 12. In the steam supply pipe 15, in order from the upstream side, a steam supply separator 16 that separates water from steam, an on-off valve 17 that opens and closes a steam path, and the like are arranged.

The steam supply pipe 15 includes a direct pipe 151 extending upward from the upper part of the steam supply separator 16, a horizontal pipe 152 extending horizontally from the upper end of the direct pipe 151 and an on-off valve 17 being arranged, and a horizontal pipe 152 downward. It is configured to include a connecting pipe 153 that is inclined to and connected to the scroll expander 3. In the present embodiment, the connection position between the directly above pipe 151 and the steam supply separator 16 which is the position where steam is taken out from the steam supply separator 16 is lower than the connection position where the steam supply pipe 15 is connected to the scroll expander 3. ing. The connection pipe 153 of the present embodiment is an L-shaped pipe having a bent portion.

<Steam exhaust pipe>
The exhaust steam pipe 18 for taking out the steam after decompression (after expansion) from the scroll expander 3 will be described. The steam exhaust pipe 18 has a first steam exhaust pipe 181 connected to the fixed scroll 50 below the connection portion between the fixed scroll 50 and the connecting pipe 153, and the fixed scroll 50 above the connecting portion between the fixed scroll 50 and the connecting pipe 153. Includes a second steam exhaust pipe 182 connected to.

Both the first exhaust steam pipe 181 and the second exhaust steam pipe 182 extend horizontally from the fixed scroll 50 and are connected to the exhaust steam separator 19. Steam is sent to the exhaust steam separator 19 through the first exhaust steam pipe 181 and the second exhaust steam pipe 182, and after the steam and water are separated by the exhaust steam separator, it is sent to a steam header for recovery (not shown).

As shown in FIG. 3, in the scroll expander 3 of the present embodiment, one or a plurality of swivel laps 32 are arranged on both side surfaces of the swivel scroll 30, and fixed scrolls 50 are arranged on both sides of the swivel scroll 30. It is a configuration to be arranged. The steam supply pipe 15 and the steam exhaust pipe 18 described above have a symmetrical shape, and are connected to a fixed scroll 50 on the back side of the paper surface, which is not shown in FIG. 2, with the same shape and number (similar configuration). There is.

<Structure of scroll expander>
Next, the configuration of the scroll expander 3 will be described. As shown in FIG. 3, the scroll expander 3 includes a housing 20, a swivel scroll 30 rotatably held in the housing 20, and a pair of fixed scrolls 50 fixed to the housing 20 so as to sandwich the swivel scroll 30. A plurality of crankshafts 70 for turning the swivel scroll 30 are provided as a main configuration.

<Housing>
The housing 20 is formed with opening holes 21 penetrating in the axial direction (horizontal direction) on both side surfaces thereof. The opening holes 21 on both sides of the housing 20 communicate with each other through a hollow portion inside the housing 20. An annular flange 22 extending inward in the radial direction is provided at the inner end of the peripheral wall of each opening hole 21.

The swivel scroll 30 is arranged inside the housing 20, and each fixed scroll 50 is fixed to both sides of the swivel scroll 30 via the flange 22. An annular hollow portion surrounding the swivel scroll 30 and the fixed scroll 50 is formed inside the housing 20, and this hollow portion serves as an accommodation space 23 for the eccentric shaft portion 71 of the crankshaft 70.

An air supply port 24 for cooling the crankshaft 70 of the accommodation space 23 is provided in the lower part of the housing 20, and an exhaust port 25 for exhausting the cooled air is provided in the upper part.

<Swirl scroll>
The swivel scroll 30 has a disc-shaped swivel side substrate portion 31, swivel laps 32 provided on both sides of the swivel side substrate portion 31, and a swivel side substrate portion 31 detachably fixed and a plurality of crankshafts 70. The swivel scroll base 33 to which is connected is provided.

The swivel lap 32 extends vertically (axially) from the plate surface of the swivel side substrate portion 31 and has a plate shape that curves in a spiral shape of an involute curve from the central portion to the outer peripheral portion of the swivel side substrate portion 31. It is composed. The swivel laps 32 on both sides have shapes corresponding to each other. At the tip of each swivel lap 32, a tip seal 34 for filling a gap between the fixed scroll 50 and the fixed side substrate portion 51 is provided. The tip seal 34 is arranged along the swirl of the swirl lap 32.

The swivel scroll base 33 is formed in a substantially triangular frame shape surrounding the swivel side substrate portion 31, and the swivel side substrate portion 31 is fixed to the inside thereof by a fastening member such as a bolt. A swivel bearing portion 35 connecting the eccentric shaft portion 71 of the crankshaft 70 is arranged at a position corresponding to the apex portion (corner portion) of the substantially triangular shape of the swivel scroll base 33.

<Fixed scroll>
Each of the fixed scrolls 50 arranged on both sides of the swivel scroll 30 is provided on a disk-shaped fixed side substrate portion 51 and a plate surface (one side) of the fixed side substrate portion 51 facing the swivel side substrate portion 31. A plurality of fixed wraps 52 and an annular outer peripheral wrap 55 surrounding the fixed wraps 52 are provided.

Each fixed-side substrate portion 51 is provided with a central opening 60 penetrating in the thickness direction at the center thereof. The central opening 60 is a through hole that communicates the outside of the scroll expander 3 with the expansion chamber 90. Further, a first opening 61 and a second opening 62 are provided on the outer peripheral side of each fixed-side substrate portion 51. The first opening 61 and the second opening 62 are in a positional relationship of facing each other in the radial direction with the central opening 60 in between. In the present embodiment, the first opening 61 is arranged below the fixed-side substrate portion 51, and the second opening 62 is arranged above the fixed-side substrate portion 51.

In the present embodiment, the downstream end of the above-mentioned steam supply pipe 15 is connected to the central opening 60, the first steam exhaust pipe 181 is connected to the first opening 61, and the second opening 62 is connected to the first exhaust pipe 181. The second steam exhaust pipe 182 is connected.

The fixed laps 52 are provided in a number, shape, and size corresponding to the swirl laps 32, extend vertically (axially) from the plate surface of the fixed-side substrate portion 51, and extend from the central portion of the fixed-side substrate portion 51. It is configured to be curved in a spiral shape of an involute curve toward the outer periphery. At the tip of each fixed lap 52, a tip seal 54 for filling a gap between the swivel scroll 30 and the swivel side substrate portion 31 is provided. The tip seal 54 is arranged along the spiral of the fixed wrap 52.

The outer peripheral wrap 55 is formed in a cylindrical shape surrounding the fixed wrap 52. The height of the outer peripheral wrap 55 substantially corresponds to the height of the fixed wrap 52. The space surrounded by the swivel-side substrate portion 31, the fixed-side substrate portion 51, and the outer peripheral wrap 55 functions as an expansion chamber 90 for expanding steam.

<Steam seal member>
Next, the steam seal member 80 for preventing the leakage of steam introduced into the expansion chamber 90 will be described. The steam seal member 80 is an annular seal member arranged at the tip of the outer peripheral wrap 55 and surrounding the expansion chamber 90 (see FIGS. 3 and 7).

FIG. 4 is an enlarged cross-sectional view showing the steam seal member 80 of the present embodiment and its vicinity. As shown in FIG. 4, the tip surface 551 of the outer peripheral wrap 55 is provided with an accommodating portion 56 for accommodating the steam seal member 80. The accommodating portion 56 is an annular groove according to the shape of the cylindrical outer peripheral wrap 55, and is configured so that the vapor seal member 80 can be arranged along the circumferential direction.

The steam seal member 80 of the present embodiment includes a first seal portion 81, a second seal portion 82 arranged on the inner peripheral side of the first seal portion 81, and a base end side (rear side) of the first seal portion 81. A spring 83, which is arranged in, is provided.

The first seal portion 81 is formed in an annular shape surrounding the expansion chamber 90 by, for example, a resin material containing PTFE (polytetrafluoroethylene) as a main component. The tip of the first seal portion 81 is in contact with the plate surface of the swivel side substrate portion 31 (the surface facing the fixed side substrate portion 51) to close the gap between the swivel side substrate portion 31 and the outer peripheral wrap 55. ..

The second seal portion 82 is, for example, an O-ring formed of fluororubber, and is for preventing the intrusion of steam (chain line in FIG. 4) from the expansion chamber 90 side to the first seal portion 81 side. The inner wall 561 on the inner peripheral side of the accommodating portion 56 is provided with a fitting groove 57 into which the second seal portion 82 is fitted. The fitting groove 57 is formed over the entire circumference of the inner wall 561 on the inner peripheral side of the accommodating portion 56. The second seal portion 82 comes into contact with the inner peripheral surface 811 of the first seal portion 81 in a state of being fitted in the fitting groove 57 and elastically deforms, so that the inner peripheral surface 811 of the first seal portion 81 and the accommodating portion 56 The gap of the inner wall 561 is sealed.

A spring accommodating portion 58 for accommodating the spring 83 is formed on the bottom surface 562 of the accommodating portion 56 (the surface of the first seal portion 81 facing the back surface 812). The spring 83 is an urging member that comes into contact with the back surface 812, which is the surface on the base end side of the first seal portion 81, and urges the tip surface 813 of the first seal portion 81 toward the swivel side substrate portion 31. The urging force of the spring 83 is adjusted so that the contact between the swivel side substrate portion 31 sliding by the swivel of the swivel scroll 30 and the tip surface 813 of the first seal portion 81 is maintained. As a material constituting the spring 83, a rubber material such as metal or fluororubber can be used, and for example, it is processed into an annular elastic member and used.

As described above, the scroll expander 3 of the present embodiment is arranged inside the housing 20 and the housing 20 provided with the air supply port 24 for the cooling air and the exhaust port 25 for the cooling air, and is on the turning side. A spiral swirl lap 32 is provided on the plate surface of the substrate portion 31, and is arranged on the plate surface of the fixed side substrate portion 51 so as to face the swivel scroll 30 whose axial direction is lateral and the swivel scroll 30 inside the housing 20. A fixed scroll 50 provided with a spiral fixed wrap 52 that meshes with the swivel wrap 32 and a tubular outer peripheral wrap 55 that surrounds the fixed wrap 52, and a concave accommodating portion 56 provided at the tip of the outer peripheral wrap 55 along the circumferential direction. A steam seal member 80 is provided as a seal member to be arranged.
The steam seal member 80 comes into contact with the swivel side substrate portion 31 in a state of being accommodated in the accommodating portion 56 to fill the gap between the swivel side substrate portion 31 and the outer peripheral wrap 55, and inside the accommodating portion 56. It has a second seal portion 82 that fills a gap between the inner peripheral side of the first seal portion 81 and the accommodating portion 56.
As a result, the second seal portion 82 can reliably prevent the intrusion of steam into the back surface side of the first seal portion 81. Since it is possible to avoid a situation in which the first seal portion 81 is pushed toward the swivel side substrate portion 31 side by the steam wrapping around to the back side and abnormal wear occurs, the sealing performance of the steam seal member 80 can be stably maintained.

Further, in the present embodiment, the steam seal member 80 is arranged in the accommodating portion 56, and further includes a spring 83 as an urging member for urging the first seal portion 81 to the swivel side substrate portion 31.
As a result, the pressing force of the first sealing portion 81 is adjusted by the spring 83 while the pressing force of the first sealing portion 81 is adjusted by the spring 83 while the second sealing portion 82 prevents steam from sneaking into the back surface side of the first sealing portion 81. Abnormal wear caused by being too strong and steam leakage caused by too weak pressing force can be prevented more reliably.

Further, in the present embodiment, the second seal portion 82 is an O-ring, and the inner wall 561 on the inner peripheral side of the accommodating portion 56 is provided with a fitting groove 57 into which the second seal portion 82 is fitted.
As a result, the second seal portion 82, which is an O-ring, is fitted into the fitting groove 57, so that the second seal portion 82 can be easily assembled at an appropriate position of the accommodating portion 56. Further, since the second seal portion 82 is held at an appropriate position by the fitting groove 57, it can sufficiently withstand a large pressure.

In the steam seal member 80 described above, an example in which the first seal portion 81 and the second seal portion 82 are formed separately has been described, but the first seal portion and the second seal portion may be integrally formed. it can. FIG. 5 is an enlarged cross-sectional view showing the steam seal member 280 of the first modification and its vicinity. The same components as those in the above embodiment are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 5, the steam seal member 280 of the first modification is configured by integrally molding the first seal portion 281 and the second seal portion 282. The first seal portion 281 is formed in a ring shape, and the second seal portion 282 is an annular rib protruding radially inward from the inner peripheral surface of the first seal portion 281. The steam seal member 280 is housed in the housing portion 56 in a state where the tip of the second sealing portion 282 is in contact with the inner wall 561 on the inner peripheral side. The first modification is also different from the above embodiment in that the fitting groove 57 is not formed on the inner wall 561.

As described above, the steam seal member 280 of the first modification is configured as a molded product in which the first seal portion 281 and the second seal portion 282 are integrally formed. Even with this configuration, it is possible to reliably prevent steam from entering the back surface side of the first seal portion 281 as in the steam seal member 80 of the above embodiment. In addition, the number of parts can be reduced to reduce the man-hours for assembly.

FIG. 6 is an enlarged cross-sectional view showing the steam seal member 380 of the second modification and its vicinity. As shown in FIG. 6, in the steam seal member 380 of the second modification, the shapes of the first seal portion 381 and the second seal portion 382 are different from those of the above embodiment and the first modification. The steam seal member 380 of the second modification may be integrally molded by combining different members such as different rubbers or integrally molding resin and rubber, or the first seal portion 381 and the second seal. The parts 382 may be prepared separately and combined to form the steam seal member 380 of the second modification.

The second seal portion 382 of the second modification has a substantially V-shaped cross section, and one side (diameter outside) of the V-shape is embedded inside the first seal portion 381, resulting in a V-shape. The tip of the other side (inner in the radial direction) protrudes inward in the radial direction from the inner peripheral surface of the first seal portion 381 and is in contact with the inner wall 561 on the inner peripheral side. Also in this second modification, the second seal portion 382 in contact with the inner wall 561 can reliably prevent steam from entering the back surface side of the first seal portion 381. Since the V-shaped groove portion is on the intrusion side of steam, the second seal portion 382 is pressed against the inner wall 561 side by the steam invading the groove portion, and good sealing performance can be exhibited. Further, as in the first modification, the number of parts can be reduced and the assembling man-hours can be reduced. In the second modification, the same material can be used for molding as in the first modification.

As described above, the first seal portion 281 and the second seal portion 282 can be made of the same material as in the first modification, or different types of rubber or resin and rubber can be used as in the second modification. It is also possible to integrally mold the steam seal member 280 by combining different members such as integral molding. Further, the steam seal member may be further arranged inside or outside in the radial direction of the steam seal members 80, 280, 380 to form a double seal structure. Further, the cross-sectional shape of the second seal portion 82, 282, 382 can be changed as appropriate. The cross-sectional shape of the second seal portion 82 can be changed to a shape other than a circle or a V shape, for example, a rectangular shape. In this way, the configuration of the steam seal member can be appropriately changed depending on the circumstances.

<Multiple crankshafts>
As shown in FIG. 3, the crankshaft 70 includes an eccentric shaft portion 71 and base shaft portions 72 arranged on both sides of the eccentric shaft portion 71. In the present embodiment, the base shaft portion 72 is provided with a weight balancer 75 that facilitates the rotation of the swivel scroll 30. The shape and weight of the weight balancer 75 are appropriately adjusted according to the mounting position of the crankshaft 70.

The eccentric shaft portion 71 is connected to the swivel scroll base 33 (swivel scroll 30), and the base shaft portion 72 is rotatably supported by the housing bearing portion 26 of the housing 20. The housing bearing portion 26 is arranged around the opening hole 21 according to the number of crankshafts 70. Each housing bearing portion 26 is a rolling bearing, and is configured by being arranged in the circumferential direction between a substantially cylindrical inner ring and an outer ring arranged concentrically and holding a large number of rolling elements. ..

FIG. 7 is a diagram schematically showing the arrangement and ventilation structure of the crankshaft 70 of the present embodiment. As shown in FIG. 7, a total of three crankshafts 70 are arranged at equal intervals in the circumferential direction, and are arranged at positions corresponding to the vertices of the downward triangle in the front view. The three crankshafts 70 have the same structure, and with the positions of the eccentric shaft portions 71 aligned, the three crankshafts 70 are synchronously rotated by a rotation synchronization mechanism (not shown) composed of a timing belt, gears, or the like. Of the three crankshafts 70, the crankshaft 70 located at the lowermost side serves as a drive shaft for transmitting a driving force to the compressor 4. The remaining two upper crankshafts 70B are driven shafts that do not directly output.

When the on-off valve 17 is opened, steam flows from the steam supply separator 16 of the steam supply pipe 15 into the expansion chamber 90 through the central opening 60 of the scroll expander 3 through the pipe 151 directly above, the horizontal pipe 152, and the connection pipe 153. (See Fig. 2). In the present embodiment, steam is supplied to the central openings 60 of the fixed scrolls 50 on both the left and right sides by the steam supply pipe 15 branching from the steam supply separator 16 (see FIG. 3). The swivel scroll 30 is swiveled by the pressure of the steam flowing into the expansion chamber 90, and the rotational driving force of the swivel scroll 30 is taken out from the lower crankshaft 70A as recovery power and transmitted to the compressor 4 via the transmission mechanism 6. (See Fig. 1).

The steam expanded in the expansion chamber 90 is discharged to the outside of the scroll expander 3 from the first opening 61 of each fixed scroll 50 through the first exhaust steam pipe 181 while expanding, and is discharged from the second opening 62 to the second. It is discharged to the outside of the scroll expander 3 through the steam exhaust pipe 182. The steam that has passed through the first exhaust steam pipe 181 and the second exhaust steam pipe 182 merges with the exhaust steam separator 19, and then the moisture is separated and sent to the steam header for recovery.

<Drain water discharge structure when stopped>
When the on-off valve 17 is closed, the supply of steam from the steam supply pipe 15 is stopped. In the present embodiment, since the on-off valve 17 is arranged not in the connecting pipe 153 inclined downward but in the horizontal pipe 152 extending in the horizontal direction, drain water flows from the upstream and collects inside the on-off valve 17 when stopped. Such a situation can be prevented. Further, since the horizontal pipe 152 of the present embodiment is located above the steam supply separator 16, drain water does not flow from the directly above pipe 151 to the horizontal pipe 152, and the drain water does not easily collect in the on-off valve 17. ing.

As shown in FIG. 3, since the scroll expander 3 is a vertically installed type in which the swivel axis is horizontally oriented, the drain water generated by condensing the steam remaining inside when stopped is collected in the lower part of the expansion chamber 90 by gravity. The drain water is discharged from the first opening 61 to the outside through the first exhaust steam pipe 181 without leaking downward by the steam seal member 80. That is, the first opening 61 functions as a path for discharging steam and also as a path for discharging drain water when stopped.

As described above, the scroll expander 3 of the present embodiment is a steam supply pipe connected to the fixed side substrate portion 51 and introducing steam to be expanded into the expansion chamber 90 formed by the swivel scroll 30 and the fixed scroll 50. 15 (connection pipe 153), a steam seal member 80 provided at the tip of the outer peripheral wrap 55 to seal the outer periphery of the expansion chamber 90, and a steam sealing member 80 connected to the fixed side substrate portion 51 to send steam discharged from the expansion chamber 90. The first opening 61 as a discharge port for communicating the first exhaust steam pipe 181 with the space inside the steam seal member 80 in the expansion chamber 90 and the first exhaust steam pipe 181 is a fixed side substrate portion 51. Formed at the bottom.
As a result, the first opening 61 is arranged near the lower limit of the expansion chamber 90 as a port on the low pressure side. Therefore, the first opening 61 functions as a steam discharge port during operation, and drain water is drained from the expansion chamber 90 when stopped. Can function as a drain water outlet for discharging water to the outside. As a result, it is possible to effectively prevent the drain water from accumulating inside the expansion chamber 90 when the water is stopped.

Further, in the present embodiment, the scroll expander 3 further includes an exhaust steam separator 19 to which the second exhaust steam pipe 182 is connected together with the first exhaust steam pipe 181, and the first exhaust steam pipe 181 is a fixed side substrate portion. It extends horizontally from 51 and is connected to the exhaust steam separator 19.
As a result, the backflow of the drain water discharged from the first opening 61 is less likely to occur, and the drain water can be stably discharged to the outside of the expansion chamber 90. The first steam exhaust pipe 181 of the present embodiment is configured to extend in the horizontal direction, but may be configured to be inclined downward.

Further, in the present embodiment, the scroll expander 3 has an on-off valve arranged between the steam supply separator 16 to which the steam supply pipe 15 is connected, the steam supply separator 16 in the steam supply pipe 15, and the fixed side substrate portion 51. 17 and are further provided. The steam supply pipe 15 is an inclined portion that inclines downward from the horizontal pipe 152 as a horizontal portion extending in the horizontal direction and the downstream end portion of the horizontal pipe 152 to the central opening 60 that is the connecting portion of the fixed side substrate portion 51. The on-off valve 17 is arranged in the horizontal pipe 152 of the steam supply pipe 15.
As a result, it is possible to effectively prevent the situation where drain water is accumulated inside the on-off valve 17, and it is possible to supply steam to the scroll expander 3 more stably.

In addition to the configuration of the present embodiment, a configuration for discharging drain water may be separately provided. For example, a drain water discharge port for discharging drain water may be formed separately from the first opening 61 on the fixed side substrate portion 51 or the outer peripheral wrap 55 of the fixed scroll 50.

<Ventilation structure of scroll expander>
Next, the ventilation structure of the scroll expander 3 will be described. As shown in FIG. 7, an air supply port 24 for cooling air is provided in the lower part of the housing 20, and an air supply duct 240 is connected to the air supply port 24. An exhaust port 25 for cooling air is provided on the upper part of the housing 20, and an exhaust duct 250 is connected to the exhaust port 25. In the present embodiment, the air supply port 24 and the exhaust port 25 are arranged side by side in the vertical direction with the fixed scroll 50 interposed therebetween.

The cooling air sent from the blower 7 through the air supply duct 240 is sent from the air supply port 24 to the inside of the housing 20 (accommodation space 23). The cooling air that has entered the inside of the housing 20 from the air supply port 24 cools the lower crankshaft 70A, and then splits into two hands along the outer circumference of the fixed scroll 50. The cooling air divided into two hands moves upward to cool each of the left and right upper crankshafts 70B, and then is exhausted to the outside of the housing 20 through the exhaust port 25.

As described above, the scroll expander 3 of the present embodiment has two upper crankshafts 70B connected to the swivel scroll 30 outside the swivel lap 32 and above the swivel center or the central opening 60, and swivel. A lower crankshaft 70A, which is outside the lap 32 and is connected to the swivel scroll 30 below the swivel center or the central opening 60 and faces the air supply port 24, is provided.
As a result, the cooling air introduced from the air supply port 24 into the accommodation space 23 of the housing 20 cools the lower crankshaft 70A and the housing bearing portion 26, and then moves along the outer periphery of the fixed scroll 50 to make a swivel lap. The two upper crankshafts 70B and the housing bearing portion 26 located outside the 32 are cooled. That is, it is possible to realize a configuration in which cooling is efficiently performed at three locations from one air supply port 24.

Further, in the present embodiment, the two upper crankshafts 70B and the lower crankshaft 70A are arranged at equal intervals in the circumferential direction of the swivel scroll 30 so as to correspond to the apex positions of the downward equilateral triangles, and are arranged on the lower side. The crankshaft 70A is located directly above the center of the air supply port 24.
As a result, after the cooling air entering the inside of the housing 20 from the air supply port 24 cools the lower crankshaft 70A, the amount of the cooling air directed to the two upper crankshafts 70B can be equalized. Cooling of each bearing can be performed efficiently.

Further, in the present embodiment, the lower crankshaft 70A is a drive shaft that transmits power.
As a result, the lower crankshaft 70A that transmits power can be reliably cooled, and the transmission of driving force can be made more stable.

In the present embodiment, the crankshaft 70 is arranged in a downward regular triangle shape, but in some cases, the direction of the triangle may be arranged diagonally. Further, although the shape of the swivel scroll base 33 is configured to be substantially triangular, the shape is not limited to this shape, and the shape such as a circular shape can be appropriately changed.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment and its modifications, and can be appropriately modified.

1 Steam utilization system 2 Steam generator 3 Scroll expander (scroll fluid machine)
5 Control device (judgment unit)
15 Steam supply pipe 16 Steam supply separator 17 On-off valve 19 Exhaust steam separator 20 Housing 24 Air supply port 25 Exhaust port 30 Swivel scroll 31 Swivel side board part 32 Swivel wrap 50 Fixed scroll 51 Fixed side board part 52 Fixed wrap 55 Outer wrap 56 Accommodating part 57 Fitting groove 80, 280, 380 Steam seal member (seal member)
81,281,381 1st seal part 82,282,382 2nd seal part 83 Spring (biasing member)
90 Expansion chamber 60 Central opening (connection part)
61 First opening (exhaust port)
152 Horizontal piping (horizontal part)
153 Inclined part (connection piping)
181 First steam exhaust pipe (steam exhaust pipe)
241 Air supply temperature sensor (Supply air temperature detector)
251 Exhaust temperature sensor (exhaust temperature detector)

Claims (4)

A scroll fluid machine that uses steam as the working fluid.
A swirl scroll with a spiral swirl lap on the plate surface of the swivel side substrate,
A fixed scroll provided with a spiral fixed wrap that meshes with the swirl wrap and a tubular outer peripheral wrap that surrounds the fixed wrap on the plate surface of the fixed side substrate portion.
A sealing member arranged along the circumferential direction is provided in the concave accommodating portion provided at the tip of the outer peripheral wrap.
The seal member is
A first seal portion that contacts the swivel side substrate portion while being housed in the accommodating portion and fills a gap between the swivel side substrate portion and the outer peripheral wrap.
A scroll fluid machine having an inner peripheral side of the first seal portion and a second seal portion that fills a gap between the accommodating portions inside the accommodating portion in a state of non-contact with the swivel side substrate portion . The seal member is
The scroll fluid machine according to claim 1, further comprising an urging member arranged in the accommodating portion and urging only the first seal portion to the swivel side substrate portion. The second seal portion is an O-ring and has an O-ring.
The scroll fluid machine according to claim 1 or 2, wherein a fitting groove for fitting the second seal portion is provided on the inner wall on the inner peripheral side of the accommodating portion. The scroll fluid machine according to claim 1 or 2, wherein the first seal portion and the second seal portion are integrally molded products.

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