JP2007009755A - Rotary expansion machine and fluid machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary expansion machine in which a suction volume can be adequately set without forming a complicated passage, and the suction volume can be changed in operation. <P>SOLUTION: The rotary expansion machine is provided with a partition vane 51 to partition an expansion chamber 32 into a high pressure side expansion chamber 32a and a low pressure side expansion chamber 32b. A suction port 41a is formed in the high pressure side expansion chamber 32a. The rotary expansion machine is provided with a closing vane 61 to close the downstream side of the suction port 41a by projecting from a vane groove 63, and a solenoid 64 to maintain the closing vane 61 sunken in the vane groove 63. The timing of releasing the closing vane 61 kept closed is controlled to control the suction volume. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotary expander that expands fluid, and a fluid machine that includes a rotary expander that expands fluid and a compressor that compresses fluid.

  Conventionally, for example, a rotary expander has been used in a refrigeration apparatus or the like. The rotary expander is arranged in a state where it is eccentric inside the cylinder, and is inserted into the inside of the piston, and a cylindrical piston that rotates (strictly revolves) while sliding on the inner peripheral surface of the cylinder. And a rotating shaft having an eccentric portion. An expansion chamber is defined in the cylinder by the piston and the cylinder inner peripheral surface. Then, when the piston rotates in the cylinder, the volume of the expansion chamber changes, and fluid is sucked into the expansion chamber and fluid is expanded in the expansion chamber.

  By the way, in order to expand the fluid, it is necessary to increase the volume of the expansion chamber after the fluid is once sucked into the expansion chamber and then the suction port is closed. That is, it is necessary to set the period for sucking the fluid into the expansion chamber, in other words, the time for opening the suction port by some means.

  Patent Documents 1 and 2 below disclose a method of setting a period during which fluid is sucked into the expansion chamber (hereinafter simply referred to as a suction period) based on the rotational position of the piston. In the rotary expander disclosed in Patent Documents 1 and 2, the front head that closes one end of the eccentric portion of the cylinder and the rotating shaft, the inflow port for introducing the refrigerant before expansion, and the groove-shaped passage communicating with the expansion chamber And are formed. On the other hand, on the front head side surface of the eccentric part of the rotating shaft, a communication path is formed to connect the inflow port and the groove-shaped path.

In the rotary expander, when the piston is in a predetermined range, the communication path overlaps with the suction port and the groove-shaped path, and the suction port communicates with the expansion chamber via the communication path and the groove-shaped path. On the other hand, if the piston is not located within the predetermined range, the communication path is separated from the suction port or the groove-shaped path, and the communication between the suction port and the expansion chamber is blocked. As described above, in the rotary expander, the period for sucking the refrigerant into the expansion chamber is set by communicating or blocking the groove-shaped passage of the front head as the piston rotates.
JP 2004-44569 A JP 2004-197640 A

  However, in the rotary expander, it is necessary to form an inflow port and a groove-like passage in the front head, and to form a communication passage in the eccentric portion of the rotating shaft. That is, a complicated flow path is separately required to suck the refrigerant into the expansion chamber. Therefore, the refrigerant suction pressure loss tends to increase.

  In the rotary expander, the period during which the refrigerant is sucked into the expansion chamber is uniquely determined by the configuration of the communication path. For this reason, the suction volume of the expander (that is, the volume of the expansion chamber at the start of expansion) cannot be changed.

  The present invention has been made in view of the above points, and one of the objects of the present invention is a rotary expander and a fluid machine capable of appropriately setting the suction period without forming a complicated flow path. Is to provide. Another object of the present invention is to provide a rotary expander capable of changing a suction volume and a fluid machine including the same.

  A rotary expander according to the present invention is a cylindrical shape that is rotatably disposed in a state of being eccentric in a cylinder having an inner peripheral surface and that is eccentric in the cylinder, and that defines an expansion chamber between the inner peripheral surface of the cylinder. And a partition member that partitions the expansion chamber into a high-pressure side and a low-pressure side, and a suction port and a discharge port that are opened and closed as the piston rotates on the high-pressure side and the low-pressure side of the expansion chamber. And a vane groove extending toward the inside of the cylinder is formed in a portion of the cylinder corresponding to the high pressure side of the expansion chamber. The vane groove is inserted into the vane groove so as to freely protrude and protrude from the vane groove. A closing vane that closes the downstream side of the suction port in the expansion chamber by contacting the outer peripheral surface of the piston, and a biasing device that biases the closing vane toward the piston, The serial confinement vanes and holding state held in the vane groove, and a release state for releasing the retention is obtained with a switchable vane holding device.

  In the rotary expander, the suction port is opened and closed as the piston rotates, and fluid is sucked into the expansion chamber through the suction port. After the fluid is inhaled, the volume of the expansion chamber increases with the rotation of the piston. Therefore, if there is no closing vane, the volume of the expansion chamber when the suction port is closed by the piston becomes the suction volume, and the suction volume is uniquely determined.

  However, the rotary expander is provided with a closing vane that closes the downstream side of the suction port in the expansion chamber. When the holding of the closed vane is released, the closed vane is urged toward the piston by the urging device and comes into contact with the outer peripheral surface of the piston. As a result, the upstream side of the confining vane in the expansion chamber is closed, and the suction of fluid into the expansion chamber (strictly, the downstream side of the confining vane) is stopped. Therefore, according to the rotary expander, the suction period can be appropriately set based on the timing for releasing the holding of the closed vane without forming a complicated flow path, and the suction volume can be appropriately set. Can be set to

  The rotary expander preferably includes a controller that controls the switching timing of the vane holding device from the holding state to the release state.

  As a result, the suction period can be adjusted during operation or during operation stop, and the suction volume can be changed. Therefore, for example, by appropriately changing the suction volume during operation, the expansion ratio can be controlled according to the operation state. Therefore, it is possible to perform advanced control on a fluid system (for example, a refrigeration apparatus) incorporating the expander.

  The vane holding device may start holding the closed vane when the piston pushes the closed vane into the vane groove as the piston rotates.

  In the rotary expander, the piston rotates and moves along the inner peripheral surface of the cylinder. Therefore, the closing vane is once pushed out of the cylinder and then pushed into the vane groove by the piston as the piston rotates. When the closing vane is pushed into the vane groove, the closing of the expansion chamber by the closing vane is released, and the fluid can be sucked into the expansion chamber through the suction port. Here, the rotational position of the piston when the closing vane is pushed in is uniquely determined. Therefore, by starting the holding of the closed vane from the time when it is pushed into the vane groove, the timing for releasing the closed vane is always constant, and the time when the fluid suction starts is set accurately.

  The rotary expander may include a permanent magnet provided on the confining vane, and the vane holding device may be constituted by a magnetic field generator.

  Alternatively, at least a part of the confining vane may be made of a magnetic material, and the vane holding device may be constituted by a magnetic field generator.

  Alternatively, the rotary expander may include an electromagnet provided on the closed vane, and the vane holding device may be configured by a magnetic field generator.

  Thereby, the holding state and the release state of the closed vane are switched depending on the presence or absence or strength of the magnetic field generated by the magnetic field generator.

  The magnetic field generator may be constituted by an electromagnet.

  The vane holding device may start holding the confining vane based on an induced current generated in the electromagnet when the confining vane is immersed in the vane groove.

  When the confining vane is immersed in the vane groove, an induced current is generated in the electromagnet. Therefore, based on this induced current, it is possible to accurately grasp the timing at which the closed vane is immersed in the vane groove. Therefore, it is possible to accurately set the switching timing from the closed vane release state to the holding state.

  An engagement portion is formed in the closed vane, and the vane holding device is engaged with the engagement portion so as to prevent protrusion of the closed vane when the closed vane is positioned in the vane groove. A mating engagement member may be provided.

  As a result, when the closing vane is positioned in the vane groove, the engaging member engages with the engaging portion of the closing vane, thereby preventing the closing vane from protruding. As a result, the confining vanes are held. On the other hand, when the engaging member is disengaged from the engaging portion of the closing vane, the closing vane protrudes from the vane groove by the biasing force from the biasing device. As a result, the closed vane is released.

  The urging device may be configured by an elastic body that is disposed in the vane groove and constantly urges the closed vane toward the piston.

  Thus, the urging device can be realized with a simple configuration. Further, the urging device can be configured at low cost.

  A hole extending toward the inner side of the cylinder is formed in a portion between the high pressure side and the low pressure side of the expansion chamber of the cylinder, and the partition member is slidably inserted into the hole. The elastic body is formed by a partition vane that protrudes toward the piston and abuts against the outer peripheral surface of the piston, and is disposed in the hole, and includes a spring that constantly biases the partition vane toward the piston. It may be formed by a spring.

  Accordingly, the partition member (partition vane) and the closing vane have the same configuration, and the parts can be shared between the partition member and the closing vane.

  The vane groove may be integrated with the hole, and the closing vane and the partition vane may both be inserted into the hole and arranged parallel to each other.

  Thus, since the partition vane and the closing vane are arranged adjacent to each other in the same hole, a space between the partition vane and the closing vane in the expansion chamber, that is, a space that does not contribute to the expansion of the fluid. Can be reduced.

  The rotary expander includes a closing member that closes one end of the cylinder in the axial direction, the suction port is formed in the closing member, and the suction vane protrudes from the vane groove when the suction vane protrudes from the vane groove. It may cover the mouth.

  As a result, the space between the confining vane and the suction port in the expansion chamber, that is, the space that does not contribute to the expansion of the fluid can be reduced.

  The fluid may be carbon dioxide.

  A fluid machine according to the present invention includes the rotary expander and a compressor having a rotation shaft connected to a rotation shaft of the rotary expander.

  In the fluid machine, since the rotary expander and the compressor are connected, the rotational speed of the rotary expander cannot be controlled independently. Therefore, the effect of the present invention that the suction volume of the expander can be changed without controlling the rotational speed is remarkably exhibited.

  The rotary shaft of the rotary expander and the rotary shaft of the compressor may be arranged coaxially, and the fluid machine may include a casing that houses both the rotary expander and the compressor.

  Thus, in the fluid machine in which the compressor and the rotary expander are integrated, the above-described effects can be obtained.

  As described above, according to the present invention, it is possible to obtain a rotary expander and a fluid machine that can appropriately set the suction period without forming a complicated flow path.

  Further, according to the present invention, the suction volume can be changed. Accordingly, for example, by changing the suction volume during operation, it is possible to perform advanced control on the fluid system incorporating the rotary expander or the fluid machine.

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

(First embodiment)
As shown in FIG. 1, the refrigeration cycle apparatus includes a refrigerant circuit 100 in which a compressor 101, a radiator 102, an expander 103, and an evaporator 104 are sequentially connected. The refrigerant circuit 100 is filled with a refrigerant that becomes a supercritical state in a high-pressure portion (a portion from the compressor 101 through the radiator 102 to the expander 103). In the present embodiment, carbon dioxide (CO ₂ ) is filled as such a refrigerant. However, the type of refrigerant is not particularly limited. The refrigerant of the refrigerant circuit 100 may be a refrigerant that does not enter a supercritical state during operation (for example, a chlorofluorocarbon refrigerant).

  Further, the refrigerant circuit in which the expander 103 is incorporated is not limited to the refrigerant circuit 100 that allows the refrigerant to flow only in one direction. The expander 103 may be provided in a refrigerant circuit capable of changing the refrigerant flow direction. For example, the expander 103 may be provided in a refrigerant circuit capable of heating operation and cooling operation by having a four-way valve or the like.

  The refrigeration cycle apparatus is provided with a controller 106 that controls the compressor 101 and the expander 103.

  The format of the compressor 101 is not limited at all. As the compressor 101, for example, a rotary compressor, a scroll compressor, or the like can be suitably used.

  The expander 103 is connected to the radiator 102 via the suction pipe 16. The expander 103 is connected to the evaporator 104 via the discharge pipe 17. The expander 103 has a built-in generator 105 that generates power using the expansion energy of the refrigerant. However, the generator 105 may be provided outside the expander 103. Further, the generator 105 is not always necessary and can be omitted.

  As shown in FIG. 2, the expander 103 is a rotary expander. The expander 103 includes a sealed container 11, a generator 105 and an expansion mechanism 20 accommodated in the sealed container 11.

  A suction pipe 16 is connected to the upper wall of the sealed container 11. The suction pipe 16 passes through the upper wall of the sealed container 11 and opens into the internal space of the sealed container 11. A terminal 18 to which an electric cable (not shown) is connected is fixed to the upper wall of the sealed container 11.

  The generator 105 includes a stator 13 fixed to the side wall of the hermetic container 11 and a rotor 14 disposed inside the stator 13. The stator 13 is connected to the terminal 18 through the wiring 9. A rotating shaft 15 is fixed to the center of the rotor 14. The rotating shaft 15 extends downward from the rotor 14. The expansion mechanism 20 is disposed below the rotation shaft 15.

  An oil reservoir 19 for storing lubricating oil is formed at the bottom of the sealed container 11. The lower end of the rotating shaft 15 is disposed in the oil reservoir 19. An oil pump (not shown) is formed at the lower end of the rotating shaft 15, and an oil supply passage (not shown) is formed inside or around the rotating shaft 15. When the rotating shaft 15 rotates, the lubricating oil in the oil reservoir 19 is pumped up by the oil pump and supplied to the sliding portion of the expansion mechanism 20 through the oil supply passage.

  The expansion mechanism 20 includes a cylinder 30 (see FIG. 3) formed in a substantially cylindrical shape, a first closing member 21 that covers the upper end of the cylinder 30, a second closing member 22 that covers the lower end of the cylinder 30, and a cylinder. And a piston 31 disposed in the interior 30.

  As shown in FIG. 3, the cylinder 30 is formed with a discharge port 44a formed on the inner peripheral surface 30a of the cylinder 30 and a discharge passage 44 extending radially outward from the discharge port 44a. The discharge pipe 17 passes through the side wall of the sealed container 11 and is connected to the discharge passage 44 of the cylinder 30.

  The piston 31 is formed in a cylindrical shape having a smaller diameter than the cylinder 30, and is disposed in the cylinder 30 so as to be freely rotatable. Strictly speaking, the term "rotation" here means that the piston 31 itself may or may not rotate. An expansion chamber 32 is defined inside the cylinder 30 by an inner peripheral surface 30 a of the cylinder 30 and an outer peripheral surface 31 a of the piston 31.

  Next to the discharge passage 44 in the cylinder 30, a vane groove 53 extending inward along the radial direction of the cylinder 30, a partition vane 51 slidably provided in the vane groove 53, and the partition vane 51 to the piston 31. There is provided a spring 52 that biases toward the surface. The spring 52 is disposed in a compressed state in the vane groove 53, and one end of the spring 52 is supported in the vane groove 53, and the other end is supported on the root portion of the partition vane 51. The partition vane 51 can protrude and retract from the cylinder 30 toward the piston 31, and is in contact with the outer peripheral surface 31 a of the piston 31. The partition vane 51 is always in contact with the piston 31 by the biasing force of the spring 52. This partition vane 51 partitions the expansion chamber 32 into a high pressure side expansion chamber 32a and a low pressure side expansion chamber 32b. The discharge port 44a of the discharge passage 44 opens into the expansion chamber 32b on the low pressure side.

  An eccentric portion 15a (see FIG. 2) of the rotary shaft 15 is inserted inside the piston 31. The eccentric portion 15 a is slidable on the inner peripheral surface of the piston 31 and is driven to rotate in accordance with the rotation of the piston 31. That is, when the refrigerant expands in the high-pressure side expansion chamber 32 a, the piston 31 that receives the expansion energy of the refrigerant rotates and moves in the cylinder 30 while being in contact with the inner peripheral surface 30 a of the cylinder 30. And the eccentric part 15a inserted in the piston 31 also rotates together with the piston 31, and as a result, the rotating shaft 15 rotates.

  As shown in FIG. 2, the first closing member 21 is formed with a suction path 41 that communicates the low pressure side expansion chamber 32 b and the internal space of the sealed container 11. The suction path 41 is a flow path for introducing the high-pressure refrigerant in the sealed container 11 into the low-pressure side expansion chamber 32b. As shown in FIG. 3, the suction port 41a, which is the downstream end opening of the suction passage 41, opens in the vicinity of the partition vane 51 in the low pressure side expansion chamber 32b. The suction port 41a opens in a direction parallel to the axial direction of the cylinder 30 (a downward direction in FIG. 2 and a front direction in FIG. 3).

  A portion of the cylinder 30 on the downstream side of the suction port 41a has a vane groove 63 extending inward along the radial direction of the cylinder 30, a closing vane 61 slidably provided in the vane groove 63, and a closing A spring 62 that biases the vane 61 toward the piston 31 is provided. The spring 62 is disposed in a compressed state in the vane groove 63, and one end of the spring 62 is supported in the vane groove 63, and the other end is supported by the root portion of the closed vane 61. In the present embodiment, the closing vane 61 is made of a magnetic material. A solenoid 64 is disposed around the vane groove 63 as a magnetic field generator. However, the type of the magnetic field generator is not limited at all, and may be other than the solenoid 64.

  As shown in FIG. 4, when the solenoid 64 is in a non-energized state, the closing vane 61 protrudes from the vane groove 63 by the biasing force of the spring 62 and abuts against the piston 31. In this case, the portion of the expansion chamber 32 a downstream of the closing vane 61 is blocked from the suction port 41 a by the closing vane 61. Therefore, even if the suction port 41a is open, the suction of the refrigerant into the expansion chamber 32a is stopped.

  On the other hand, as shown in FIG. 3, when a current is passed through the solenoid 64 when the closed vane 61 is immersed in the vane groove 63, a magnetic field is generated in the vane groove 63, and the closed vane 61 Is held in the vane groove 63. That is, when the solenoid 64 is energized, a force that opposes the biasing force of the spring 62 is applied to the closing vane 61, and the protrusion of the closing vane 61 is prevented. In this case, the refrigerant flows into the expansion chamber 32a (specifically, downstream of the closed vane 61) through the suction port 41a.

  Therefore, in the present expander 103, by switching between energization and non-energization of the solenoid 64 during one rotation of the piston 31, the closed vane 61 is held in the vane groove 63 (holding state) and the holding is performed. By releasing, the state (release state) in which the closed vane 61 protrudes from the vane groove 63 can be appropriately switched.

  Next, the operation of the expander 103 will be described. As shown in FIG. 2, in the present expander 103, the high-pressure refrigerant sucked from the suction pipe 16 is once released into the internal space of the sealed container 11. The high-pressure refrigerant in the sealed container 11 flows through the suction path 41 of the first closing member 21 and flows into the expansion chamber 32a from the suction port 41a.

  As shown in FIG. 3, the piston 31 rotates from the partition vane 51 side toward the closing vane 61 side (counterclockwise direction in FIG. 3). At this time, the suction port 41 a is opened and closed by the piston 31 as the piston 31 rotates. That is, when the piston 31 is in a position where the suction port 41a is closed (a position where the suction port 41a and the piston 31 overlap vertically), the suction of the refrigerant from the suction port 41a is stopped, and the piston 31 closes the suction port 41a. When it is in a position not to be used, the refrigerant is sucked from the suction port 41a.

  Further, in the present expander 103, when the piston 31 reaches a predetermined rotational position after opening the suction port 41a, the controller 106 stops energization of the solenoid 64 and releases the holding state of the closing vane 61. As a result, the closing vane 61 protrudes from the vane groove 63 and comes into contact with the piston 31. Thereby, the suction of the refrigerant into the expansion chamber 32 is stopped even though the suction port 41a itself is not closed.

  In the present expander 103, the time when the piston 31 opens the suction port 41a is the time when the suction of the expansion chamber 32 starts, and the time when the closing vane 61 protrudes and contacts the piston 31 is when the suction of the expansion chamber 32 ends. Become. The period from the start of inhalation to the end of inhalation is the inhalation period. Further, the volume of the expansion chamber 32a (strictly, the downstream side of the closing vane 61) when the closing vane 61 comes into contact with the piston 31 becomes the suction volume. Therefore, the suction period and the suction volume can be controlled based on the timing at which the holding of the closed vane 61 is released.

  After completing the suction of the refrigerant, the volume of the high-pressure side expansion chamber 32a increases as the piston 31 rotates. Thereby, the refrigerant expands in the high pressure side expansion chamber 32a, and the pressure of the refrigerant decreases. When the piston 31 further rotates, the high pressure side expansion chamber 32a continues to the discharge port 44a and becomes the low pressure side expansion chamber 32b. As a result, the refrigerant in the expansion chamber 32b is discharged to the discharge passage 44 through the discharge port 44a. Then, the low-pressure refrigerant discharged to the discharge passage 44 is discharged to the outside of the expander 103 through the discharge pipe 17.

  As described above, the piston 31 rotates and moves in the cylinder 30 while being in contact with the inner peripheral surface 30 a of the cylinder 30. For this reason, when the piston 31 reaches a predetermined position (position on the upper left in FIG. 3), the closing vane 61 is pushed into the vane groove 63 by the piston 31. In the present embodiment, when the closing vane 61 is pushed into the vane groove 63, an electric current is supplied to the solenoid 64 and the holding of the closing vane 61 is started.

  By the way, in this embodiment, when the closing vane 61 is pushed into the vane groove 63, an induced current is generated in the solenoid 64. Therefore, by detecting this induced current, it is possible to detect the time when the closing vane 61 is pushed into the vane groove 63, in other words, the time when the piston 31 reaches the predetermined position. Therefore, in the present embodiment, switching from the released state to the held state is performed based on the induced current.

  As described above, according to the present embodiment, the refrigerant suction period can be set based on the timing of releasing the holding of the closed vane 61 (specifically, the timing of stopping energization of the solenoid 64). it can. Therefore, the suction volume can be appropriately set based on the timing when the holding of the confining vane 61 is released.

  The suction volume may be set to a constant design value, but the suction volume may be changed during operation or during operation stop. In the present expander 103, the timing for releasing the holding of the closed vane 61 can be freely adjusted, so that the suction volume can be freely controlled. For example, during operation of the refrigeration cycle apparatus, the controller 106 may adjust the suction volume of the expansion mechanism 20 to sequentially control the expansion ratio. If the suction volume is changed during operation in this way, it is possible to perform advanced control on the refrigeration cycle apparatus. If the optimum or suitable expansion ratio is selected according to the operating state of the refrigeration cycle apparatus, the operating efficiency can be improved.

  In this embodiment, the partition member that partitions the expansion chamber 32 into the high-pressure side expansion chamber 32 a and the low-pressure side expansion chamber 32 b is formed by the partition vane 51. However, the partition member is not limited to the partition vane 51. However, as in this embodiment, by using the partition vane 51 as the partition member and making the partition vane 51 and the closing vane 61 have the same configuration, the parts can be shared. In other words, a conventionally used partition vane can be used as the closing vane 61 as it is.

  In the present embodiment, the closing vane 61 is made of a magnetic material, and the closing vane 61 is held by an electromagnetic force generated between the solenoid 64 and the closing vane 61. However, as shown in FIG. 5, a permanent magnet 65 may be attached to the closing vane 61. In this case, the closed vane 61 can be formed of a nonmagnetic material, and various materials can be selected as the material of the closed vane 61.

  In addition, as shown in FIG. 6, the magnetic field generator may be constituted by a permanent magnet 66 and an electromagnet 67 may be provided on the closing vane 61. Even in such a case, the closing vane 61 can be held using electromagnetic force.

(Second Embodiment)
As shown in FIGS. 7 and 8, the second embodiment is obtained by changing the position of the closing vane 61 in the first embodiment.

  In the present embodiment, the closing vane 61 and the partition vane 51 are inserted into the same vane groove 53. In other words, the vane groove for the closing vane 61 is integrated with the vane groove 53 of the partition vane 51. The closing vane 61 and the partition vane 51 are arranged in parallel to each other.

  The closing vane 61 is provided on the downstream side (left side in FIG. 7) of the expansion chamber 32 a with respect to the partition vane 51. As shown in FIG. 8, the closing vane 61 is disposed at a position overlapping the suction port 41 a when viewed from the axial direction of the rotating shaft 15. In other words, the closing vane 61 is disposed at a position so as to cover the suction port 41a by the closing vane 61 itself. Therefore, when the closing vane 61 protrudes from the vane groove 53, the suction port 41 a is directly closed by the closing vane 61. The closed vane 61 is disposed at a position overlapping the suction port 41a when viewed from the axial direction, but is disposed downstream of the suction port 41a with respect to the refrigerant flow direction.

  Other configurations are substantially the same as those of the first embodiment.

  In the present embodiment, since the suction port 41a is closed by the closing vane 61, the space between the suction port 41a and the closing vane 61 in the high-pressure side expansion chamber 32a can be omitted. That is, a useless space that does not contribute to the expansion of the refrigerant can be eliminated in the high-pressure side expansion chamber 32a. Therefore, a large maximum value of the volume of the high-pressure side expansion chamber 32a partitioned by the confining vanes 61 can be secured. Therefore, the control range of the suction volume can be expanded.

  In particular, in this embodiment, since the closing vane 61 and the partition vane 51 are disposed adjacent to each other in the same vane groove 53, the space between the closing vane 61 and the partition vane 51 in the high-pressure side expansion chamber 32a. Can be made substantially zero. Therefore, the useless space that does not contribute to the expansion of the refrigerant can be made substantially zero.

(Third embodiment)
As shown in FIG. 9, the third embodiment is a modification of the vane holding device.

  In the present embodiment, the cylinder 30 is formed with a communication hole 71 that communicates the vane groove 63 and the inside of the sealed container 11. A sliding pin 72 is inserted into the communication hole 71. A movable iron core 73 is attached to one end side of the sliding pin 72, and a coil 74 of a solenoid 75 is wound around the movable iron core 73. A fixed iron core 76 is disposed on the movable iron core 73 on the sliding pin 72 side. The movable iron core 73 or the sliding pin 72 is constantly urged to the side opposite to the closing vane 61 side (left side in FIG. 9A) by urging means (not shown) such as a spring. A hole 77 is formed in the side surface of the closing vane 61. In FIG. 9, the illustration of the spring 62 (see FIG. 3) that biases the closing vane 61 is omitted.

  As shown in FIG. 9B, when a current is passed through the coil 74 of the solenoid 75, the movable iron core 73 is attracted to the fixed iron core 76. As a result, the sliding pin 72 is inserted into the hole 77 of the closing vane 61. When the sliding pin 72 is thus inserted into the hole 77, the movement of the closing vane 61 is restricted, and the closing vane 61 is held in a state of being immersed in the vane groove 63.

  On the other hand, as shown in FIG. 9A, when the energization of the coil 74 of the solenoid 75 is stopped, the sliding pin 72 is urged to the side opposite to the closing vane 61 by a spring or the like (not shown). The pin 72 is removed from the hole 77. As a result, the closing vane 61 becomes slidable in the vane groove 63, and the holding state of the closing vane 61 is released.

  Therefore, the above-described effects can be obtained also in this embodiment.

  In the present embodiment, the actuator that drives the sliding pin 72 uses electromagnetic force. However, the actuator is not limited to one that uses electromagnetic force. For example, a motor, an electric cylinder, or the like can be used as the actuator. Alternatively, an actuator that drives the sliding pin 72 using the differential pressure of the fluid may be used. A fluid pressure cylinder or the like can be used as such an actuator. For example, it is also possible to drive the slide pin 72 by using a high-pressure refrigerant before expansion and a low-pressure refrigerant after expansion and using the differential pressure between these refrigerants.

  In this embodiment, the hole 77 of the closing vane 61 forms an engaging portion, and the engaging member that engages with the engaging portion is formed by the sliding pin 72. However, the engaging portion and the engaging member of the closing vane 61 are not limited to the hole 77 and the sliding pin 72 as long as they prevent the closing vane 61 from protruding. .

(Fourth embodiment)
Next, an embodiment of a fluid machine according to the present invention will be described. As shown in FIG. 10, the fluid machine 110 according to the present embodiment is a fluid machine 110 in which an expander and a compressor are integrated.

  The fluid machine 110 includes a sealed container 11, an expansion mechanism 20 that is accommodated in the sealed container 11, an electric motor 120, and a compression mechanism 80. The expansion mechanism 20, the electric motor 120, and the compression mechanism 80 are arranged in order from the top to the bottom.

  The compression mechanism 80 is a rotary compression mechanism. However, the compression mechanism 80 is not limited to the rotary type, and may be another rotary compression mechanism such as a scroll type compression mechanism.

  The compression mechanism 80 includes a substantially cylindrical cylinder 81, an upper closing member 82 that covers the upper end of the cylinder 81, a lower closing member 83 that covers the lower end of the cylinder 81, and a cylindrical shape that is rotatably disposed in the cylinder 81. The piston 84 is provided.

  Inside the cylinder 81, a compression chamber 87 is defined by the inner peripheral surface of the cylinder 81 and the outer peripheral surface of the piston 84. A vane groove 93 extending in the radial direction is formed in the cylinder 81, and a vane 89 that contacts the piston 84 and a spring 90 that biases the vane 89 toward the piston 84 are provided in the vane groove 93. . An eccentric portion 85a of the rotary shaft 85 is slidably inserted into the piston 84. When the rotary shaft 85 rotates, the piston 84 is rotationally driven by the eccentric portion 85 a and rotates in the cylinder 81 while being in contact with the inner peripheral surface of the cylinder 81. As a result, the volume of the compression chamber 87 changes, and the refrigerant is compressed in the compression chamber 87.

  A suction pipe 91 for sucking low-pressure refrigerant is connected to the lower side of the side wall of the sealed container 11. The suction pipe 91 is inserted into the upper closing member 82, and a suction path 86 that guides the refrigerant from the suction pipe 91 to the compression chamber 87 is formed inside the upper closing member 82. The upper closing member 82 is formed with a discharge flow path 88 that allows the compression chamber 87 and the internal space of the sealed container 11 to communicate with each other. A discharge pipe 92 is connected to the central portion in the vertical direction of the side wall of the sealed container 11. The discharge pipe 92 opens into the internal space of the sealed container 11. With such a configuration, the low-pressure refrigerant in the suction pipe 91 is sucked into the compression chamber 87 through the suction passage 86, compressed in the compression chamber 87, and then discharged to the internal space of the sealed container 11 through the discharge passage 88. Is done. Then, the high-pressure refrigerant in the sealed container 11 is discharged from the discharge pipe 92.

  The electric motor 120 includes a stator 121 and a rotor 122, and a rotating shaft 85 is fixed to the rotor 122. The rotation shaft 85 is coaxially connected to the rotation shaft 15 of the expansion mechanism 20. Therefore, the rotating shaft 15 and the rotating shaft 85 rotate integrally. In this embodiment, the rotation shaft 15 of the expansion mechanism 20 and the rotation shaft 85 of the compression mechanism 80 are formed as separate members. However, the rotation shaft 15 and the rotation shaft 85 are formed integrally with the same member. May be.

  The configuration of the expansion mechanism 20 is substantially the same as that of the first embodiment. Description of the expansion mechanism 20 is omitted. The inside of the sealed container 11 is partitioned by the second closing member 22 of the expansion mechanism 20. That is, an expansion-side high-pressure space is formed above the second closing member 22, and a compression-side high-pressure space is formed below the second closing member 22. However, it goes without saying that a partition member separate from the second closing member 22 may be provided in the sealed container 11.

  Also in this embodiment, the same effect as that of the first embodiment can be obtained. That is, the suction volume of the expansion mechanism 20 can be set freely. Further, the suction volume can be changed, and the expansion ratio can be controlled.

  In the fluid machine 110, the rotation shaft 15 of the expansion mechanism 20 rotates integrally with the rotation shaft 85 of the compression mechanism 80. Therefore, the rotation speed of the expansion mechanism 20 and the rotation speed of the compression mechanism 80 are always equal, and the rotation speed of the expansion mechanism 20 cannot be controlled independently of the rotation speed of the compression mechanism 80. However, as described above, in the fluid machine 110, the suction volume of the expansion mechanism 20 can be controlled by adjusting the timing for releasing the holding of the closed vane 61. Therefore, the expansion ratio of the expansion mechanism 20 can be freely controlled regardless of the rotation speed of the compression mechanism 80.

  In the present embodiment, the expansion mechanism 20 is disposed above the compression mechanism 80, but the expansion mechanism 20 may be disposed below the compression mechanism 80. That is, the compression mechanism 80 may be disposed on the upper side of the sealed container 11 and the expansion mechanism 20 may be disposed on the lower side.

  In the present embodiment, the rotary shaft 15 and the rotary shaft 85 extend in the vertical direction, and the expansion mechanism 20, the electric motor 120, and the compression mechanism 80 are arranged in the vertical direction. However, the sealed container 11 may be formed in a horizontal type. That is, the rotation shaft 15 and the rotation shaft 85 may be arranged in the left-right direction, and the expansion mechanism 20, the electric motor 120, and the compression mechanism 80 may be arranged in the left-right direction.

(Other embodiments)
In the above embodiment, the expansion mechanism 20 is provided with only one cylinder. However, the expansion mechanism 20 may include a plurality of cylinders.

  In the embodiment, the closing vane 61 is pushed into the vane groove 63 by the rotating piston 31. However, it is also possible to pull the closing vane 61 into the vane groove 63 by electromagnetic force.

  In the embodiment, the biasing device that biases the closing vane 61 is formed by the spring 62. However, the biasing device may be an elastic body other than the spring 62. Further, the urging device is not limited to an elastic body, and may generate an urging force by, for example, electrostatic force or magnetic force.

  As described above, the present invention is useful for a rotary expander and a fluid machine having the rotary expander.

Refrigerant circuit diagram of refrigerant circuit The longitudinal cross-sectional view of the expander which concerns on 1st Embodiment Cross-sectional view of expansion mechanism with confined vane immersed (cross-sectional view taken along line III-III in FIG. 2) Cross section of expansion mechanism with confined vane protruding Configuration diagram of a variation of the vane holding device Configuration of another modification of vane holding device It is a transverse cross section of the expander concerning a 2nd embodiment, and a figure of the state where a closed vane was immersed It is a transverse cross section of an expander concerning a 2nd embodiment, and a figure of the state where a closed vane protruded (A) And (b) is a block diagram of the vane holding | maintenance apparatus which concerns on 3rd Embodiment. A longitudinal sectional view of a fluid machine according to a fourth embodiment

Explanation of symbols

30 cylinder 31 piston 32 expansion chamber 41a suction port 44a discharge port 51 partition vane (partition member)
61 Containment vane 62 Spring (biasing device)
63 Vane groove 64 Solenoid (vane holding device, magnetic field generator)

Claims (16)

A cylinder having an inner peripheral surface;
A cylindrical piston that is rotatably arranged in an eccentric state in the cylinder, and defines an expansion chamber between the cylinder and an inner peripheral surface;
A partition member that partitions the expansion chamber into a high pressure side and a low pressure side,
On the high-pressure side and the low-pressure side of the expansion chamber, a suction port and a discharge port that are opened and closed as the piston rotates are formed, respectively.
A portion of the cylinder corresponding to the high pressure side of the expansion chamber is formed with a vane groove extending toward the inside of the cylinder.
A closed vane that is inserted into the vane groove so as to be freely retractable, protrudes from the vane groove and contacts the outer peripheral surface of the piston, thereby closing the downstream side of the suction port in the expansion chamber;
A biasing device that biases the confining vane toward the piston;
A rotary expander comprising: a vane holding device capable of switching between a holding state in which the closed vane is held in the vane groove and a release state in which the holding is released.   The rotary expander according to claim 1, further comprising a controller that controls a switching timing of the vane holding device from a holding state to a release state.   The rotary type according to claim 1 or 2, wherein the vane holding device starts holding the closed vane when the piston pushes the closed vane into the vane groove as the piston rotates. Expansion machine. A permanent magnet provided on the confining vane;
The rotary expander according to any one of claims 1 to 3, wherein the vane holding device is configured by a magnetic field generator. At least a portion of the confining vane is made of a magnetic material,
The rotary expander according to any one of claims 1 to 3, wherein the vane holding device is configured by a magnetic field generator. Comprising an electromagnet provided on the confining vane;
The rotary expander according to any one of claims 1 to 3, wherein the vane holding device is configured by a magnetic field generator.   The rotary expander according to any one of claims 4 to 6, wherein the magnetic field generator is configured by an electromagnet.   The rotary expander according to claim 7, wherein the vane holding device starts holding the closed vane based on an induced current generated in the electromagnet when the closed vane is immersed in the vane groove. An engagement portion is formed on the confining vane,
The said vane holding | maintenance apparatus is provided with the engaging member engaged with the said engaging part so that protrusion of the said closing vane may be prevented, when the said closing vane is located in the said vane groove | channel. The rotary expander as described in any one of -3.   The rotary device according to claim 1, wherein the biasing device is configured by an elastic body that is disposed in the vane groove and constantly biases the closed vane toward the piston. Type expander. A hole extending toward the inside of the cylinder is formed in a portion between the high pressure side and the low pressure side of the expansion chamber of the cylinder,
The partition member is slidably inserted into the hole, and is formed by a partition vane that protrudes from the hole toward the piston and contacts the outer peripheral surface of the piston.
A spring disposed in the hole and constantly biasing the partition vane toward the piston;
The rotary expander according to claim 10, wherein the elastic body is formed by a spring. The vane groove is integrated with the hole;
The rotary expander according to claim 11, wherein the closed vane and the partition vane are both inserted into the hole and arranged in parallel to each other. A closing member that closes one end of the cylinder in the axial direction;
The inlet is formed in the closing member,
The rotary expander according to any one of claims 1 to 11, wherein the confining vane covers the suction port when protruding from the vane groove.   The rotary expander according to any one of claims 1 to 13, wherein the fluid is carbon dioxide. The rotary expander according to any one of claims 1 to 14,
A compressor having a rotating shaft coupled to a rotating shaft of the rotary expander;
A fluid machine equipped with. The rotary shaft of the rotary expander and the rotary shaft of the compressor are arranged coaxially,
The fluid machine according to claim 15, further comprising a casing that accommodates both the rotary expander and the compressor.

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