JP5984492B2 - Fluid machinery - Google Patents

Description

  The present invention relates to a fluid machine used by being incorporated in a Rankine cycle or the like, and more particularly to a fluid machine including an expander that generates power by expansion of a refrigerant and a piston pump that pumps the refrigerant.

  As a fluid machine incorporated in the Rankine cycle, there is known a pump-integrated expander in which an expander that generates power by expansion of a refrigerant and a pump that pumps the refrigerant are integrally connected (for example, see Patent Document 1). . The inventors are considering adopting a piston pump with high volumetric efficiency from a low rotation range to a high rotation range as the pump in this type of fluid machine. In this case, there is a concern that the liquid-phase refrigerant sucked into the piston pump flows into the crank chamber and the lubrication state of each sliding portion in the crank chamber is deteriorated.

  On the other hand, Patent Document 2 discloses a liquid phase in which a lubricating oil is separated from a gas-phase refrigerant in a fluid machine incorporated in a Rankine cycle, and the separated lubricating oil is sucked into a refrigerant pump. A technique for sufficiently lubricating the mechanical sliding portion of the pump for pumping the refrigerant by supplying the refrigerant is disclosed.

JP 2010-077827 A Japanese Patent No. 4725344

  However, since the lubricating oil separated from the gas-phase refrigerant is hotter than the refrigerant sucked by the pump, the lubricating oil separated from the gas-phase refrigerant is sucked into the refrigerant pressure-feeding pump as in the prior art. If supplied to the liquid phase refrigerant, a part of the refrigerant sucked by the pump is gasified (evaporated), and the volumetric efficiency of the pump may be reduced.

  Therefore, the present invention provides a fluid machine including an expander that generates power by expansion of a refrigerant and a piston pump that pumps the refrigerant, and reduces the lubrication performance of the mechanical sliding portion in the crank chamber of the piston pump. It aims at reducing the possibility that the volumetric efficiency of a piston pump will fall, suppressing.

A fluid machine according to one aspect of the present invention includes an expander that generates power by expansion of a refrigerant, and a piston pump that pumps liquid phase refrigerant, and a refrigerant outlet chamber in which the expanded refrigerant is discharged from the expander. And the crank chamber of the piston pump communicate with each other.

  According to the fluid machine described above, the refrigerant outlet portion from which the refrigerant after expansion is discharged from the expander communicates with the crank chamber of the piston pump, so that the crank chamber is at a low pressure and the liquid-phase refrigerant is easily gasified. Therefore, the amount of the liquid refrigerant flowing into the crank chamber and / or storing in the crank chamber can be reduced. Moreover, there is almost no possibility of gasifying the refrigerant sucked in the pump as in the prior art. Thereby, the possibility that the volumetric efficiency of the piston pump may be reduced can be reduced while suppressing a decrease in the lubrication performance of the mechanical sliding portion of the piston pump.

It is a figure which shows schematic structure of the waste heat recovery apparatus in 1st Embodiment of this invention. It is sectional drawing of the fluid machine (pump integrated expander) in the said 1st Embodiment. It is a figure which shows an example of the distribution path | route of the gaseous-phase refrigerant | coolant in the fluid machine (pump integrated expander) in the said 1st Embodiment. It is a figure which shows the modification of the fluid machine (pump integrated expander) in the said 1st Embodiment. It is a figure which shows schematic structure of the waste heat recovery apparatus in 2nd Embodiment of this invention. It is sectional drawing of the fluid machine (Expansion machine, pump, generator motor integrated fluid machine) in the said 2nd Embodiment. It is a figure which shows an example of the distribution path | route of the gaseous-phase refrigerant | coolant in the fluid machine (Expansion machine, pump, generator motor integrated fluid machine) in the said 2nd Embodiment. It is a figure which shows the modification of the fluid machine (Expansion machine, pump, generator motor integrated fluid machine) in the said 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 shows a schematic configuration of an exhaust heat recovery apparatus 1A to which a fluid machine according to the present invention is applied in the first embodiment. The exhaust heat recovery apparatus 1A is mounted on a vehicle and recovers and uses the exhaust heat of the engine 10 of the vehicle.

  The exhaust heat recovery apparatus 1A includes a Rankine cycle 2A that recovers exhaust heat of the engine 10 and converts it into power, a transmission mechanism 3 that transmits power between the Rankine cycle 2A and the engine 10, and an exhaust heat recovery apparatus 1 And a control unit 4A for controlling the entire operation.

  The engine 10 is a water-cooled internal combustion engine, and is cooled by engine cooling water that circulates in the cooling water passage 11. A heater 22 of a Rankine cycle 2A, which will be described later, is disposed in the cooling water flow path 11, and engine cooling water that has absorbed heat from the engine 10 flows through the heater 22.

Rankine cycle 2A collects exhaust heat of engine 10 as an external heat source (here, heat of engine cooling water), converts it into power, and outputs it.
A heater 22, an expander 23, a condenser 24, and a pump 25 are arranged in this order in the refrigerant circuit 21 of the Rankine cycle 2A. In addition, a bypass path 26 is provided between the heater 22 and the condenser 24 to bypass the expander 23 and distribute the refrigerant. The bypass path 26 is a bypass that opens and closes the bypass path 26. A valve 27 is provided.

  The heater 22 is a heat exchanger that heats the refrigerant into superheated steam by exchanging heat between the engine coolant that has absorbed heat from the engine 10 and the refrigerant of the Rankine cycle 2A. Although not shown, the heater 22 may be configured to perform heat exchange between the exhaust of the engine 10 and the refrigerant instead of the engine cooling water.

The expander 23 is a scroll expander that generates power (driving force) by expanding the refrigerant (gas-phase refrigerant) that has been heated by the heater 22 into superheated steam and converting it into rotational energy.
The condenser 24 is a heat exchanger that cools and condenses (liquefies) the refrigerant by causing heat exchange between the refrigerant that passes through the expander 23 and the outside air.

  The pump 25 is a mechanical piston pump that pumps the refrigerant (liquid phase refrigerant) liquefied by the condenser 24. The pump 25 sucks and discharges the refrigerant (liquid phase refrigerant) liquefied by the condenser 24, so that the refrigerant circulates through each of the elements of the Rankine cycle 2A.

  Here, it is configured as a “pump-integrated expander” 29A in which an expander (scroll expander) 23 and a pump (piston pump) 25 are integrally connected. That is, the rotary shaft 28 of the pump-integrated expander 29A has a function as an output shaft of the expander 23 and a function as a drive shaft of the pump 25.

  The transmission mechanism 3 includes a pulley 32 attached to the rotary shaft 28 of the pump-integrated expander 29A via an electromagnetic clutch 31, a crank pulley 33 attached to the crankshaft 12 of the engine 10, a pulley 32, and a crank pulley 33. And a belt 34 wound around the belt.

The control unit 4A controls the operation of the bypass valve 27 and the electromagnetic clutch 31.
When the control unit 4A opens the bypass valve 27, the refrigerant circulates around the expander 23. Further, when the control unit 4 controls the electromagnetic clutch 31 to be ON (engaged) / OFF (released), the transmission mechanism 3 is connected to the engine 10 and Rankine cycle 2A (more specifically, the pump-integrated expander 29A). Power can be transmitted / interrupted between them.

When starting the Rankine cycle 2A, the control unit 4A opens the bypass valve 27 and turns on (engages) the electromagnetic clutch 31 to drive the pump 25 by the engine 10. Thereby, the refrigerant is circulated around the expander 23. For example, when the pressure difference before and after the expander 23 becomes a predetermined value or more, the bypass valve 27 is closed and the refrigerant is circulated through the expander 23. Thereafter, when the expander 23 generates a sufficient driving force, a part of the driving force generated by the expander 23 drives the pump 25, and the remaining driving force is transmitted to the engine 10 via the transmission mechanism 3. This is transmitted to assist the output (driving force) of the engine 10.
The control unit 4A can stop the Rankine cycle 2A by turning off (releasing) the electromagnetic clutch 31, for example.

Next, the structure of the pump-integrated expander 29A (fluid machine) will be described.
FIG. 2 is a sectional view of the pump-integrated expander 29A. As described above, the pump-integrated expander 29A is a fluid machine in which the expander 23 that generates power by expansion of the refrigerant and the pump 25 that pumps the refrigerant are integrally connected, and is incorporated in the Rankine cycle 2A. Used.

  The pump-integrated expander 29A includes a pump unit 50A constituting the pump (piston pump) 25, an expansion mechanism 60A constituting the expander (scroll expander) 23, and a function and expansion as a drive shaft of the pump unit 50A. A rotary shaft 28 having a function as an output shaft of the machine part 60A and a housing 70 for housing them are provided. The pump-integrated expander 29 </ b> A includes an electromagnetic clutch 31 and a pulley 32 that constitute the transmission mechanism 3.

The rotary shaft 28 extends in the axial direction of the housing 70 (left-right direction in the figure), and has a crank portion 28a whose axis is offset (offset) from the rotation center of the rotary shaft 28, and a large-diameter end portion 28b. have.
In the housing 70, bearings 71a and 71b for rotatably supporting the rotary shaft 28 are disposed. The bearing 71a is disposed in a cylindrical portion 70a that is formed so as to protrude from one end side (here, the left end side) of the housing 70, and supports the vicinity of the end portion of the rotating shaft 28 opposite to the large-diameter end portion 28b. The bearing 7 b is disposed substantially at the center in the axial direction of the housing 70 and supports the large-diameter portion 28 b of the rotating shaft 28.

  The crank portion 28 a of the rotating shaft 28 is accommodated in a crank chamber 72 </ b> A formed in the housing 70. Further, a shaft seal 73 is provided on the crank chamber 72A side of the bearing 71a of the cylindrical portion 70a of the housing 70 to seal between the outer peripheral surface of the rotary shaft 28 and the inner peripheral surface of the cylindrical portion 70a. .

  An armature plate 81 is attached to an end portion (tip portion) of the rotating shaft 28 protruding outside from the cylindrical portion 70a, and the pulley 32 can be rotated via a bearing 82 on the outer peripheral surface of the cylindrical portion 70a. Is attached. A clutch coil 83 is accommodated in an annular groove 32 a formed on the end surface of the pulley 32. The electromagnetic clutch 31 includes an armature plate 81 and a clutch coil 83. When the clutch coil 83 is energized, the armature plate 81 is magnetically attracted to the end face of the pulley 32, and the electromagnetic clutch 31 is fastened.

Next, the pump unit 50A will be described.
The pump portion 50A is rotated by a piston 51 housed in a pump cylinder 74A formed in communication with the crank chamber 72A, one end connected to the piston 51 and the other end connected to the crank portion 28a of the rotary shaft 28. And a connecting rod 52 that converts the rotational motion of the shaft 28 into the reciprocating linear motion of the piston 51.

  The open end of the pump cylinder 74 </ b> A is covered with a cylinder cover 75. The cylinder cover 75 is formed with a suction port 75a for sucking the refrigerant (liquid phase refrigerant) liquefied by the condenser 24 into the pump cylinder 74A and a discharge port 75b for discharging the sucked refrigerant. The intake port 75a is provided with a check valve 76a that allows only refrigerant to be sucked, and the discharge port 75b is provided with a check valve 76b that allows only refrigerant to be discharged.

  The pump unit 50A repeatedly sucks and discharges the refrigerant (liquid phase refrigerant) as the piston 51 reciprocates in the pump cylinder 74A as the rotary shaft 28 rotates, thereby pumping the refrigerant.

Next, the expander unit 60A will be described.
The expander portion 60A includes a fixed scroll 61 fixed to an end portion (right end portion in the drawing) opposite to the tubular portion 70a of the housing 70, and a turning scroll 62.
The fixed scroll 61 has a disk-shaped base 61a and a spiral wrap 61b erected on one surface (the left surface in the figure) of the base 61a. A refrigerant inlet 61c is formed through the substantially central portion of the base 61a of the fixed scroll 61. The orbiting scroll 62 has a substantially disc-shaped base portion 62a and a spiral wrap 62b erected on the surface of the base portion 62a on the fixed scroll 61 side.

  The fixed scroll 61 and the orbiting scroll 62 are arranged so that the spiral wraps 61b and 62b mesh with each other, and an expansion chamber that expands the introduced refrigerant (gas phase refrigerant) between the wraps 61b and 62b. 63 is formed. Further, between the surface opposite to the fixed scroll 61 side of the base portion 62a of the orbiting scroll 62 and the opposing surface of the housing 70 facing this, rotation prevention such as ball coupling that prevents the orbiting scroll 62 from rotating is provided. A member 77 is disposed.

  In the expander unit 60A, the refrigerant (gas-phase refrigerant) introduced into the expansion chamber 63 through the inlet 61c expands in the expansion chamber 63, so that the orbiting scroll 62 performs an orbiting motion with respect to the fixed scroll 61. . The expansion chamber 63 moves from the central portion to the peripheral portion with the turning motion of the orbiting scroll 62, and the expanded refrigerant (gas phase refrigerant) is discharged to the refrigerant outlet chamber 78A in the housing 70. The The refrigerant outlet chamber 78A is a space formed on the radially outer side of the orbiting scroll 62 in the housing 70, for example.

  In the housing 70, the pump unit 50 </ b> A and the expander unit 60 </ b> A are connected via a driven crank mechanism 80. Specifically, the large-diameter portion 28 b of the rotating shaft 28 is connected to the orbiting scroll 62 via the driven crank mechanism 80.

  The driven crank mechanism 80 includes a flange portion 81 fixed to the end face of the large-diameter portion 28b of the rotary shaft 28, and a rotary shaft erected at a position shifted from the rotation center of the rotary shaft 28 on the end face of the flange portion 81. 28, and a crankpin 82 parallel to 28, and an eccentric bush 83 provided on the orbiting scroll 62 side. The eccentric bush 83 is disposed via a bearing 84 in a hollow boss portion 62 c formed on a surface of the base portion 62 a of the orbiting scroll 62 opposite to the fixed scroll 61 side.

  The crank pin 82 is inserted through an insertion hole 83 a formed in the eccentric bush 83. The insertion hole 83 a is formed at a position shifted from the center of the bush, and the eccentric bush 83 is configured to be swingable around the crank pin 82. Thereby, in the driven crank mechanism 80, the turning motion of the crank pin 82 becomes the turning motion of the eccentric bush 83 as it is, and conversely, the turning motion of the eccentric bush 83 becomes the turning motion of the crank pin 82 as it is.

  The driven crank mechanism 80 converts the rotary motion of the rotary shaft 28 into the rotary motion of the orbiting scroll 62, or converts the rotary motion of the orbiting scroll 62 into the rotary motion of the rotary shaft 28. And as above-mentioned, the pump part 50 is driven by rotation of the rotating shaft 28, and a liquid phase refrigerant is pumped.

  A counterweight (balance weight) 85 is fixed to the eccentric bush 83 in order to balance the eccentric bush 83 and the orbiting scroll 62 and suppress the occurrence of vibrations in the expander unit 60A. Further, the swing range of the eccentric bush 83 around the crankpin 82 is restricted by the engagement between the restriction hole 81 a provided in the flange portion 81 and the restriction protrusion 83 b provided in the eccentric bush 83.

Here, in the housing 70, the crank chamber 72 </ b> A on the pump unit 50 </ b> A side and the refrigerant outlet chamber 78 </ b> A on the expander unit 60 </ b> A side accommodate the bearing 71 b that supports the large-diameter portion 28 b of the rotary shaft 28 and the driven crank mechanism 80. In other words, the housing 70 communicates with the rotation preventing member 77 through a gap space between the pump unit 50A and the expander unit 60A. Further, an outlet port 79A through which the expanded refrigerant discharged from the expander unit 60A to the refrigerant outlet chamber 78A flows out to the condenser 24 side is opened to the crank chamber 72A.
The outlet port 79A is preferably formed so as to open to the bottom of the crank chamber 72A (the lower part in the vertical direction of the pump-integrated expander 29A).

  As a result, in the pump-integrated expander 29A, as indicated by an arrow in FIG. 3, the gas phase refrigerant discharged (after expansion) from the expander portion 60A to the refrigerant outlet chamber 78A is rotated by the rotation prevention member 77 and the driven member. It passes through the accommodation space of the crank mechanism 80 and the bearing 71b, and then flows out from the outlet port 79A via the crank chamber 72A. The gas-phase refrigerant flowing out from the outlet port 79A is liquefied by the condenser 24 and then pumped by the pump unit 50A.

  According to the pump-integrated expander 29A (fluid machine) described above, the refrigerant outlet chamber 78A from which the expanded gas-phase refrigerant is discharged from the expander section 60A (expander) and the crank of the pump section 50A (piston pump). Since the chamber 72A is in communication, the crank chamber 72A can be set to a low pressure so that the liquid refrigerant can be easily gasified, and the liquid phase flows into the crank chamber 72A and / or is stored in the crank chamber 72A. The amount of refrigerant can be reduced. As a result, a decrease in the lubrication performance of the mechanical sliding portion in the crank chamber 72A of the pump portion 50A and an increase in the stirring resistance of the liquid phase refrigerant by the rotating shaft 28 (crank portion 28b) are suppressed, and the mechanical sliding portion As well as improving the durability, mechanical loss can be reduced.

Further, the outlet port 79A is opened at the bottom (lower part) of the crank chamber 72A, and even when the liquid phase refrigerant flows into the crank chamber 72A, the flowing liquid phase refrigerant is discharged from the outlet port 79A. Storage of the crank chamber 72A is suppressed.
Further, since the high-temperature expanded gas-phase refrigerant is configured to flow outside (on the condenser 24 side) via the crank chamber 72A, the liquid-phase refrigerant is stored in the crank chamber 72A. Alternatively, most of the liquid-phase refrigerant can be gasified and discharged (discharged) from the outlet port 79A as a gas-phase refrigerant. Thereby, the fall of the lubrication performance of the mechanical sliding part of 50 A of pump parts, and the increase in the stirring resistance of the liquid phase refrigerant | coolant by the rotating shaft 28 can further be suppressed.

  Furthermore, the crank chamber 72A and the refrigerant outlet chamber 78A are communicated with each other in the housing 70 through a bearing 71b that rotatably supports the rotary shaft 28 and a rotation prevention member 77 that prevents rotation of the orbiting scroll 62. There is no need to newly form a dedicated communication path or the like for communicating the crank chamber 72A and the refrigerant outlet chamber 78A. Thereby, the enlargement of the pump-integrated expander 29A and an increase in manufacturing cost can be suppressed.

  Here, in the above-described pump-integrated expander 29A, an outlet port 79A through which the expanded refrigerant flows out to the condenser 24 side is opened in the crank chamber 72A, and the expanded air discharged from the expander unit 60 is discharged. The phase refrigerant is configured to flow out to the outside (condenser 24 side) via the crank chamber 72A. However, the crank chamber 72A and the refrigerant outlet chamber 78A only need to communicate with each other, and the position where the outlet port 79A is formed is not limited to the configuration according to the above embodiment.

  For example, as shown in FIG. 4, an outlet port 79A is opened in the refrigerant outlet chamber 72A, and / or the crank chamber 72A communicates with a space on the expander unit 60A side such as a storage space of the driven crank mechanism 80. The passage 91 may be formed in the housing 70. Even in this case, the pressure in the crank chamber 72A can be reduced and the liquid refrigerant can be easily gasified. Therefore, the amount of the liquid refrigerant flowing into the crank chamber 72A and / or stored in the crank chamber 72A. Can be reduced.

  When the outlet port 79A is opened in the refrigerant outlet chamber 72A, as indicated by an arrow in FIG. 4A, the refrigerant gasified in the crank chamber 72A is transferred to the bearing 71b and the rotation prevention member. 77 is supplied to the refrigerant outlet portion 78A through the housing space 77 and the rotation prevention member 77, and flows out from the outlet port 79A (to the condenser 24 side) together with the expanded gas phase refrigerant. In addition, when the communication path 91 that connects the crank chamber 72A and the space on the expander section 60A side such as the accommodation space of the driven crank mechanism 80 is formed in the housing 70, as shown in FIG. The expanded refrigerant passes through the bearing 71b and the communication passage 70a, and then flows out from the outlet port 79A via the crank chamber 72A.

  Further, a communication path for directly communicating the crank chamber 72A and the refrigerant outlet chamber 78A may be formed in the housing 70, or a communication path for communicating the outlet port 79A and the refrigerant outlet chamber 78A in the configuration shown in FIGS. May be formed in the housing 70. Further, these communication paths may be provided outside the housing 70. Even in this case, the pressure in the crank chamber 72A can be reduced and the liquid refrigerant can be easily gasified. Therefore, the amount of the liquid refrigerant flowing into the crank chamber 72A and / or stored in the crank chamber 72A. Can be reduced.

Next, a second embodiment of the present invention will be described.
FIG. 5 shows a schematic configuration of an exhaust heat recovery apparatus 1B to which the fluid machine according to the present invention is applied in the second embodiment.
The exhaust heat recovery apparatus 1A in the first embodiment drives the pump 25 that circulates the refrigerant of the Rankine cycle 2A by the driving force generated by the expander 23, and assists the output of the engine 10. The Rankine cycle 2A incorporates a pump-integrated expander 29A.

  On the other hand, the exhaust heat recovery apparatus 1B according to the second embodiment includes the generator motor 100 and drives the generator motor 100 with the driving force generated by the expander 23, thereby converting the exhaust heat of the engine 10 into electric energy. And use it. The Rankine cycle 2B incorporates an expander, a pump and a generator motor integrated fluid machine 29B. In this embodiment, the transmission mechanism 3 in the first embodiment is not provided, and the pump 25 is driven by the generator motor 100. In FIG. 5, the same elements as those in FIG. 1 are denoted by the same reference numerals, and the functions thereof are also the same.

  In FIG. 5, the exhaust heat recovery apparatus 1B includes a Rankine cycle 2B, a generator motor 100, and a control unit 4B.

  A heater 22, an expander 23, a condenser 24, and a pump 25 are arranged in this order in the refrigerant circulation path 21 of the Rankine cycle 2B. In addition, a bypass path 26 is provided between the heater 22 and the condenser 24 to bypass the expander 23 and distribute the refrigerant. The bypass path 26 is a bypass that opens and closes the bypass path 26. A valve 27 is provided.

  The generator motor 100 is connected to the power storage device 102 via a power conversion unit (rectifier, inverter, etc.) 101. The generator motor 100 is disposed between the expander 23 and the pump 25 and is driven by electric power supplied from the power storage device 102 or driven by the driving force generated by the expander 23.

  The control unit 4B controls the operation of the bypass valve 27 and the power supply / power supply stop from the power storage device 102 to the generator motor 100. When power is supplied from the power storage device 102 to the generator motor 100, the generator motor 100 operates as an electric motor to drive the pump 25. On the other hand, when power supply from the power storage device 102 to the generator motor 100 is stopped, the generator motor 100 operates as a generator and is driven by the driving force generated by the expander 23 to generate power.

  When starting the Rankine cycle 2B, the control unit 4B opens the bypass valve 27 and supplies power from the power storage device 102 to the generator motor 100 to operate the generator motor 100 as an electric motor to drive the pump 25. Thereby, the refrigerant is circulated around the expander 23. The control unit 4B closes the bypass valve 27 and circulates the refrigerant via the expander 23, for example, when the pressure difference across the expander 23 reaches or exceeds a predetermined value. Thereafter, when the expander 23 generates a sufficient driving force, the control unit 4B stops the power supply from the power storage device 102 to the generator motor 100 and operates the generator motor 100 as a generator. As a result, the driving force generated by the expander 23 drives the pump 25 and the generator motor 100 to generate power. The power generated by the generator motor 100 is supplied to the power storage device 102 via the power converter 101.

  Here, in the present embodiment, the expander 23, the pump (piston pump) 25, and the generator motor 100 are configured as a fluid machine 29 </ b> B integrally connected by a common rotating shaft 105. That is, the rotating shaft 105 of the fluid machine 29B has a function as an output shaft of the expander 23, a function as a drive shaft of the pump 25, and a function as a drive shaft of the generator motor 100.

Next, the structure of the fluid machine 29B in which the expander 23, the pump (piston pump) 25, and the generator motor 100 are integrally connected will be described.
FIG. 6 is a cross-sectional view of the fluid machine 29B.
As shown in FIG. 6, the fluid machine 29 </ b> B includes a pump unit 50 </ b> B constituting a pump (piston pump) 25, a generator motor unit 110 constituting a generator motor 100, and an expansion constituting a expander (scroll expander) 23. The structure part 60B, a rotary shaft 105 having a function as a drive shaft of the pump part 50B, a function as a drive shaft of the generator motor part 110, and a function as an output shaft of the expander part 60B, and a housing 120 for housing them .

The housing 120 includes a first housing 121 that houses the pump unit 50B and the generator motor unit 110, a second housing 122 that houses the expander unit 60B, and a connecting member 123 that connects the first housing 121 and the second housing 122. Have. Specifically, the first housing 121 is fitted and fixed to one side (left side in the figure) of the connecting member 123, and the second housing 122 is fitted and fixed to the other side (right side in the figure) of the connecting member 123. ing.
A through hole 123 a is formed in the connecting member 123, and the internal space of the first housing 121 and the internal space of the second housing 122 communicate with each other through the through hole 123 a.

  The rotation shaft 105 extends in the first housing 121 in the axial direction (left-right direction in the drawing), and the shaft center is shifted (offset) from the rotation center of the rotation shaft 105 on one end side (left-end side in the drawing). E) It has a crank portion 105a. The rotating shaft 105 is rotatably supported by a bearing 131 a disposed in the first housing 121 and a bearing 131 b held by the connecting member 123. The crank portion 105 a of the rotating shaft 105 is accommodated in a crank chamber 72 </ b> B formed in the first housing 121.

  The pump part 50B is rotated by a piston 51 housed in a pump cylinder 74B formed in communication with the crank chamber 72B, one end connected to the piston 51 and the other end connected to the crank part 105a of the rotary shaft 105. And a connecting rod 52 that converts the rotational movement of the shaft 105 into the reciprocating linear movement of the piston 51. The open end of the pump cylinder 74B is covered with a cylinder cover 75 in which a suction port 75a and a discharge port 75b are formed, as in the first embodiment. The intake port 75a and the discharge port 75b are provided with check valves 76a and 76b, respectively.

  The pump unit 50B repeatedly sucks and discharges the refrigerant (liquid phase refrigerant) as the piston 51 reciprocates in the pump cylinder 74B as the rotating shaft 105 rotates, thereby pumping the refrigerant.

The generator motor unit 110 is disposed in a space (accommodating space) adjacent to the crank chamber 72B in the first housing 121 via a bearing 131a.
The generator motor unit 110 includes a rotor (rotor) 111 made of, for example, a permanent magnet fixed to the rotation shaft 105, and a stator 112 fixed to the inner peripheral surface of the first housing 121 so as to surround the rotor 111. Prepare.

  The stator 112 includes a yoke 112a and, for example, three sets of coils 112b wound around the yoke 112a. The coil 112b generates a magnetic field that rotates the rotor 111 when a three-phase alternating current is supplied from the power storage device 102 via the power conversion unit 101, whereby the rotating shaft 105 rotates and the pump unit 50B is driven. Is done. In addition, the coil unit 112 b generates a three-phase alternating current along with the rotation of the rotor 111, and the generated three-phase alternating current is supplied to the power storage device 102 via the power conversion unit 101. Thereby, the power storage device 102 is charged.

  The expander unit 60B includes a fixed scroll 61 and a turning scroll 62, as in the first embodiment. The fixed scroll 61 is fixed in the second housing 122, and an introduction hole 122 a for introducing the refrigerant into the second housing 122 is formed in the second housing 122.

  The fixed scroll 61 has a disk-shaped base 61a and a spiral wrap 61b erected on one surface (the left surface in the figure) of the base 61a. A refrigerant inlet 61c is formed through the substantially central portion of the base 61a of the fixed scroll 61. The orbiting scroll 62 has a substantially disc-shaped base portion 62a and a spiral wrap 62b erected on the surface of the base portion 62a on the fixed scroll 61 side.

  The fixed scroll 61 and the orbiting scroll 62 are arranged so that the spiral wraps 61b and 62b mesh with each other, and an expansion chamber 63 for expanding the introduced gas-phase refrigerant is formed between the wraps 61b and 62b. Is done. Here, in the present embodiment, a space 122b having a relatively large volume is formed on the back side of the fixed scroll 61 in the second housing 122 (the side opposite to the orbiting scroll 61). Even when the refrigerant introduced from 122a includes a liquid-phase refrigerant (that is, in a gas-liquid mixed state), the liquid-phase refrigerant is introduced into the inlet 61c formed in the base 61a of the fixed scroll 61 and thus into the expansion chamber 63. Is suppressed.

  Further, between the surface opposite to the fixed scroll 61 side of the base 62a of the orbiting scroll 62 and the opposing surface of the connecting member 123 facing this, rotation such as ball coupling that prevents the orbiting scroll 62 from rotating is provided. A blocking member 77 is arranged.

  In the expander unit 60B, the gas-phase refrigerant expands through an introduction hole 122a formed in the second housing 122, a space 122b on the back side of the fixed scroll 61, and an introduction port 61c formed in the base 61a of the fixed scroll 61. It is introduced into the chamber 63. The introduced gas-phase refrigerant expands in the expansion chamber 63, so that the orbiting scroll 62 performs an orbiting motion with respect to the fixed scroll 61. The expansion chamber 63 moves from the central portion to the peripheral portion in accordance with the orbiting motion of the orbiting scroll 62, and the expanded refrigerant (gas phase refrigerant) enters the refrigerant outlet chamber 78B in the second housing 122. Discharged. The refrigerant outlet chamber 78B is a space formed on the radially outer side of the orbiting scroll 62 in the second housing 122, for example.

The rotating shaft 105 extending in the axial direction in the first housing 121 is connected to the orbiting scroll 62 through a driven crank mechanism 80.
The driven crank mechanism 80 is erected at a position shifted from the rotation center of the rotary shaft 28 of the flange portion 81 fixed to the end surface of the rotary shaft 105 and the end surface of the flange portion 81, as in the first embodiment. , A crankpin 82 parallel to the rotary shaft 28, and an eccentric bush 83 provided on the orbiting scroll 62 side.

  The eccentric bush 83 is disposed via a bearing 84 in a hollow boss portion 62 c formed on a surface of the base portion 62 a of the orbiting scroll 62 opposite to the fixed scroll 61 side. The crank pin 82 is inserted through an insertion hole 83 a formed in the eccentric bush 83. The insertion hole 83 a is formed at a position shifted from the center of the bush, and the eccentric bush 83 is configured to be swingable around the crank pin 82.

  Further, a counterweight (balance weight) 85 is fixed to the eccentric bush 83 in order to balance the eccentric bush 83 and the orbiting scroll 62 and to suppress the occurrence of vibration in the expander unit 60B. Further, the swing range of the eccentric bush 83 around the crank pin 82 is restricted by the engagement of the restriction hole 81 a provided in the flange portion 81 and the restriction protrusion 83 b provided in the eccentric bush 83.

  The driven crank mechanism 80 converts the rotary motion of the rotary shaft 105 into the rotary motion of the orbiting scroll 62, or converts the rotary motion of the orbiting scroll 62 into the rotary motion of the rotary shaft 105. And as above-mentioned, the pump part 50B is driven by rotation of the rotating shaft 105, and a liquid phase refrigerant is pumped.

Here, in the housing 120, the crank chamber 72 </ b> B on the pump unit 50 </ b> B side and the refrigerant outlet chamber 78 </ b> B on the expander unit 60 </ b> B side include a bearing 131 b that supports the rotating shaft 105, a generator motor unit 110 (particularly the rotor 111 and the stator 112. And the through hole 123a formed in the connecting member 123 and the rotation prevention member 77.
Further, an outlet port 79B through which the expanded refrigerant flows out to the condenser 24 side is open to the crank chamber 72B. The outlet port 79B is preferably formed so as to open to the bottom of the crank chamber 72B (the lower part in the vertical direction of the fluid machine 29B).

  Thereby, in the fluid machine 29B according to the present embodiment, as shown by an arrow in FIG. 7, the gas phase refrigerant discharged (after expansion) from the expander unit 60B to the refrigerant outlet chamber 78B is rotated by the rotation prevention member 77, It passes through the through hole 123a formed in the connecting member 123, the generator motor section 110 (the gap space between the rotor 111 and the stator 112), and the bearing 131b, and then flows out from the outlet port 79B via the crank chamber 72B. . And the gaseous-phase refrigerant | coolant which flowed out from the exit port 79B is liquefied by the condenser 24, and is pumped by the pump part 50B after that.

  Also in the fluid machine 29B in the second embodiment described above, the refrigerant outlet chamber 78B from which the expanded refrigerant (gas phase refrigerant) is discharged from the expander unit 60B (expander), and the pump unit 50B (piston pump). Since the crank chamber 72B communicates with the crank chamber 72B, an effect similar to that of the fluid machine (pump-integrated expander 29A) in the first embodiment can be obtained.

  That is, since the crank chamber 72B can be set to a low pressure so that the liquid refrigerant can be easily gasified, the amount of the liquid refrigerant flowing into the crank chamber 72B and / or stored in the crank chamber 72B can be reduced. Can do. Further, even when the liquid phase refrigerant flows into the crank chamber 72B, the flowing liquid phase refrigerant is prevented from being discharged from the outlet port 79B and stored in the crank chamber 72B. Furthermore, since the high-temperature expanded gas-phase refrigerant is configured to flow out to the outside via the crank chamber 72B, even when the liquid-phase refrigerant is stored in the crank chamber 72B, Most of the gas can be gasified and discharged (discharged) from the outlet port 79B as a gas-phase refrigerant.

  In the fluid machine 29B in the above embodiment, the outlet port 79B through which the expanded refrigerant flows out to the condenser 24 side opens in the crank chamber 72B. However, the present invention is not limited to this. The crank chamber 72 </ b> B and the refrigerant outlet chamber 78 </ b> B only need to communicate with each other. For example, as illustrated in FIG. 8, the outlet port 29 </ b> B may open into the accommodation space of the generator motor unit 110 of the first housing 121. In addition, an outlet port 79B may be opened in the refrigerant outlet chamber 72B, and a communication path communicating with the housing space of the generator motor unit 90 and the crank chamber 72B may be formed in the first housing 121.

  Furthermore, a communication path that directly connects the crank chamber 72B and the refrigerant outlet chamber 78B may be formed in the housing 120 (the first housing 121, the second housing 122, and the connecting member 123), or the outlet in the configuration shown in FIG. A communication path that allows the port 79B and the refrigerant outlet chamber 78B to communicate with each other may be formed in the housing 120. Further, these communication paths may be provided outside the housing 120. Even in this case, the pressure in the crank chamber 72A can be reduced and the liquid refrigerant can be easily gasified. Therefore, the amount of the liquid refrigerant flowing into the crank chamber 72A and / or stored in the crank chamber 72A. Can be reduced.

  Moreover, although the fluid machine 29B in the said embodiment has the expander 23, the pump (piston pump) 25, and the generator motor 100 connected integrally, the generator motor 100 is good also as a generator. In this case, it is preferable that the exhaust heat recovery apparatus 1 </ b> B includes the transmission mechanism 3 as in the exhaust heat recovery apparatus 1 </ b> A in the first embodiment so that the pump 25 can be driven by the engine 10.

  By the way, the fluid machine which was applied to Rankine cycle and was equipped with the expander which expands a gaseous-phase refrigerant | coolant and generate | occur | produces motive power, and the piston pump which pumps a liquid phase refrigerant | coolant was demonstrated. However, the technical idea of the present invention can also be applied to the case where the expander and the piston pump are configured separately. In this case, in the Rankine cycle, the piston pump crank chamber that pumps the liquid phase refrigerant communicates with the outlet side of the expander, for example, the piston pump crank chamber and the refrigerant flow from the expander to the condenser. What is necessary is just to provide the communicating path which connects a path | route.

  1A, 1B ... Waste heat recovery device, 2A, 2B ... Rankine cycle, 10 ... Engine, 21 ... Refrigerant circuit, 22 ... Heater, 23 ... Expander, 24 ... Condenser, 25 ... Pump (piston pump), 28 Rotating shaft, 29A ... Pump-integrated expander (fluid machine), 29B ... Expander / pump / generator / motor-integrated fluid machine, 50A, 50B ... Pump section, 51 ... Piston, 52 ... Connecting rod, 60A, 60b ... Expander unit, 61 ... fixed scroll, 62 ... orbiting scroll, 71a, 71b ... bearing (bearing part), 70 ... housing, 72A, 72B ... crank chamber, 77 ... rotation prevention member, 78A, 78B ... refrigerant outlet chamber, 79A 79B ... exit port, 80 ... passive crank mechanism, 91 ... communication path, 100 ... generator motor, 105 ... rotary shaft, 110 ... generator motor part, 1 ... rotor, 112 ... stator, 130 ... housing

Claims (8)

An expander that generates power by expansion of the refrigerant;
A piston pump for pumping liquid phase refrigerant,
A fluid machine, wherein a refrigerant outlet chamber from which the expanded refrigerant is discharged from the expander communicates with a crank chamber of the piston pump.
  2. The fluid machine according to claim 1, wherein the refrigerant outlet chamber and the crank chamber communicate with each other in a housing that houses the expander and the piston pump.   The fluid machine according to claim 2, wherein the expanded refrigerant discharged from the expander to the refrigerant outlet chamber is discharged to the outside of the casing through the crank chamber.   The refrigerant outlet chamber and the crank chamber communicate with each other via a bearing portion that rotatably supports a rotary shaft that functions as an output shaft of the expander and a drive shaft of the piston pump. The fluid machine according to claim 2 or 3. The expander is a scroll expander;
5. The fluid machine according to claim 4, wherein the refrigerant outlet chamber and the crank chamber communicate with each other via a rotation prevention member that prevents rotation of the orbiting scroll in the bearing portion and the scroll expander.   The fluid machine according to any one of claims 1 to 3, wherein a communication passage is provided for communicating the refrigerant outlet chamber and the crank chamber.   The fluid machine according to any one of claims 1 to 6, wherein a generator motor is provided between the expander and the piston pump.   The fluid machine according to claim 7, wherein the refrigerant outlet chamber and the crank chamber communicate with each other via the generator motor.