JP5969226B2 - Fluid machinery - Google Patents

Description

  The present invention relates to a fluid machine having a drive unit that is driven by a working fluid sucked from a suction port, and discharging the working fluid that has passed through the drive unit from a discharge port.

  2. Description of the Related Art Conventionally, as a fluid machine, a fluid machine integrally including a bypass path that guides a working fluid (refrigerant) sucked from a suction port to a discharge port by bypassing a drive unit, and a valve mechanism that opens and closes the bypass path (For example, see Patent Document 1).

JP 2010-236360 A

However, the bypass path of the conventional fluid machine bypasses the drive unit and circulates the working fluid. However, the working fluid bypassing the drive unit has a sliding part such as a rotation prevention mechanism (ball coupling) of the drive unit. After passing through the portion to be arranged, it is discharged from the discharge port.
For this reason, if the working fluid that circulates bypassing the drive unit is in a liquid phase, the liquid phase working fluid (liquid refrigerant) flows through the sliding unit, so that the lubricating oil in the sliding unit is caused to flow. There was a possibility that the lubricity of the sliding part was lowered.

  Therefore, the present invention provides a fluid machine that can suppress a decrease in lubricity of the sliding portion even when the working fluid is in a liquid phase when the working fluid is circulated by bypassing the drive portion. The purpose is to do.

In order to achieve the above object, a fluid machine according to the present invention includes a suction port into which a working fluid that has become high-pressure heating steam flows, a drive unit that is driven by expansion of the working fluid sucked from the suction port, A fluid machine having a discharge port through which a low-pressure working fluid flows out through the drive unit, the working fluid sucked from the suction port bypassing the sliding part of the fluid machine and the drive unit A bypass path leading to the discharge port is provided , and the bypass path directly connects the suction port and the discharge port.
The fluid machine according to the present invention includes a suction port into which a working fluid that has become high-pressure heated steam flows, a drive unit that is driven by the expansion of the working fluid sucked from the suction port, and a passage that passes through the drive unit. And a discharge port through which the low-pressure working fluid flows out, wherein the suction port and the discharge port extend in the radial direction of the rotary shaft of the drive unit, and the axial direction of the rotary shaft And a bypass path that leads the working fluid sucked from the suction port to the discharge port by bypassing the sliding portion and the drive portion of the fluid machine. And a valve mechanism for opening and closing the bypass path, wherein the valve mechanism is configured to open and close the bypass path by displacing a valve body in a radial direction of a rotation shaft of the drive unit.

  According to the fluid machine of the present invention, the bypass passage bypasses the sliding portion together with the drive portion and circulates the working fluid, so that even when the working fluid is in a liquid phase, the lubricating oil of the sliding portion is allowed to flow. Therefore, it can suppress that lubricity falls.

It is a figure which shows schematic structure of the waste heat utilization apparatus in embodiment of this invention. It is sectional drawing which shows the pump integrated expander integrated in the said waste heat utilization apparatus. It is a partial expanded sectional view which shows the bypass part which comprises the said pump integrated expander.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
FIG. 1 shows a waste heat utilization apparatus 1A for a vehicle in which an expander as a fluid machine is incorporated.
The waste heat utilization apparatus 1A is an apparatus that is mounted on a vehicle together with the engine 10 and collects and uses the waste heat of the engine 10.

The waste heat utilization apparatus 1A includes a Rankine cycle apparatus 2A, a transmission mechanism 3 that transmits the output of the Rankine cycle apparatus 2A to the engine 10, and a control unit 4.
The engine 10 is an internal combustion engine provided with a water-cooled cooling device, and the cooling device includes a cooling water circulation path 11 for circulating cooling water.
The cooling water circulation path 11 is provided with the evaporator 22 of the Rankine cycle device 2A, and the cooling water that has absorbed heat from the engine 10 passes through the evaporator 22 and then returns to the engine 10 again.

Rankine cycle device 2 </ b> A collects waste heat of engine 10 from the cooling water of engine 10, converts the recovered heat into driving force, and outputs the driving force.
The Rankine cycle device 2A includes a circulation path 21 that circulates a working fluid, and an evaporator 22, an expander 23, a condenser 24, and a pump 25A are disposed in this circulation path 21 in this order along the flow direction of the working fluid. It is.
As the working fluid (refrigerant), for example, a fluid based on a skeleton made of fluorocarbon is used, and lubricating oil circulates together with the working fluid, and lubrication, sealing, and cooling in the sliding portions of the expander 23 and the pump 25A are performed. Take a role such as.

The evaporator 22 heats and evaporates (vaporizes) the working fluid by causing heat exchange between the high-temperature cooling water that has absorbed heat from the engine 10 and the working fluid of the Rankine cycle device 2A.
The expander 23 (fluid machine) is a device that generates a driving force by expanding the working fluid that has been vaporized by the evaporator 22 and that has reached a high temperature and a high pressure. As an example, a scroll expander is used.

The condenser 24 cools and condenses (liquefies) the working fluid by exchanging heat between the working fluid that has passed through the expander 23 and has a low pressure and the outside air.
The pump 25 </ b> A is a mechanical pump and pumps the working fluid liquefied by the condenser 24 to the evaporator 22.
As described above, the working fluid circulates in the circulation path 21 while repeating vaporization, expansion, and condensation.

Here, the expander 23 and the pump 25 </ b> A are connected and integrated by the rotation shaft 28, thereby providing a pump-integrated expander 29 </ b> A (fluid machine). 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 drive shaft of the pump 25A.
The Rankine cycle device 2A is activated by first driving the pump 25A with the output of the engine 10, and then when the expander 23 generates a sufficient driving force, the driving force of the expander 23 is changed to the pump 25A. Will come to drive.

The transmission mechanism 3 transmits the torque (shaft torque) of the pump-integrated expander 29A, which is the output of the Rankine cycle device 2A, to the engine 10, and at the time of startup of the Rankine cycle device 2A, the output torque of the engine 10 is This is transmitted to the body expander 29A (pump unit).
The transmission mechanism 3 includes a pulley 31 attached to the rotating shaft 28 of the pump-integrated expander 29A, a crank pulley 32 attached to the crankshaft 10a of the engine 10, a belt 33 wound around the pulley 31 and the crank pulley 32, And an electromagnetic clutch 34 provided between the rotary shaft 28 and the pulley 31 of the pump-integrated expander 29A.

Then, by turning on (engaging) / off (releasing) the electromagnetic clutch 34, transmission and interruption of power between the engine 10 (crankshaft 10a) and the rotary shaft 28 of the pump-integrated expander 29A are switched.
The control unit 4 including a microcomputer has a function of controlling the electromagnetic clutch 34, and controls the operation / stop of the Rankine cycle device 2A by controlling the electromagnetic clutch 34 on / off.

That is, when the control unit 4 determines that the operating condition of the Rankine cycle device 2A is satisfied, the electromagnetic clutch 34 is engaged (turned on) and the pump 25A is operated by the engine 10 to circulate the working fluid (refrigerant). Start the Rankine cycle device 2A.
When the expander 23 is activated to generate a driving force, a part of the driving force generated by the expander 23 drives the pump 25A, and the remaining driving force is transferred to the engine via the transmission mechanism 3. 10 and assists the output (driving force) of the engine 10.

Further, when the operating condition of the Rankine cycle device 2A is not satisfied, the control unit 4 releases (turns off) the electromagnetic clutch 34 and stops the circulation of the working fluid, thereby stopping the Rankine cycle device 2A. Let
The evaporator 22 can be a device that exchanges heat between the working fluid of the Rankine cycle device 2A and the exhaust of the engine 10, and also exchanges heat with the cooling water of the engine 10. At the same time, a device for exchanging heat with the exhaust of the engine 10 can be provided.

Further, as will be described later, the expander 23 is integrally provided with a bypass path for circulating the working fluid by bypassing the scroll section as a drive section, and a valve mechanism for opening and closing the bypass path.
And the control unit 4 controls the valve mechanism to be opened to open the bypass path immediately after the start of the Rankine cycle device 2A to which the electromagnetic clutch 34 is engaged, for example, to bypass the scroll of the expander 23, and to supply the working fluid. Try to circulate.

Thereafter, for example, when the refrigerant temperature at the inlet of the expander 23 exceeds a threshold value, in other words, when the expander 23 can generate a driving force, the control unit 4 controls the valve mechanism to be closed. Then, the bypass path is closed, and the working fluid is switched to a state of circulating through the scroll.
Thus, if the working fluid is circulated by bypassing the scroll of the expander 23 immediately after the start of the Rankine cycle device 2A, the pressure in the evaporator 22 decreases and the evaporation temperature of the working fluid decreases. Therefore, the startability of the Rankine cycle device 2A can be improved. Further, when the Rankine cycle device 2A is stopped, when the electromagnetic clutch 34 is released (turned off), the bypass path is opened in order to prevent high rotation due to the residual pressure.

Next, the structure of the pump-integrated expander 29A will be described in detail with reference to FIG.
As described above, the pump-integrated expander 29A includes the pump 25A that circulates the working fluid of the Rankine cycle apparatus 2A, and the expander 23 that generates a rotational driving force by the expansion of the working fluid heated and vaporized by the evaporator 22. Are fluid machines that are driven by a common rotating shaft 28, and include a pulley 31 and an electromagnetic clutch 34 that constitute the transmission mechanism 3.

The expander 23 of the pump-integrated expander 29A includes a fixed scroll 51 disposed at one end in the axial direction of the pump-integrated expander 29A and a orbiting scroll that is combined to be eccentrically engaged with the fixed scroll 51 ( A movable scroll) 52, a housing portion 54 having a discharge port 53, and a casing portion 56 having a suction port 55.
The fixed scroll 51 includes a disk-shaped main body 51a, a scroll portion (spiral body) 51b standing in a rib shape on one end surface of the main body 51a, and a working fluid formed so as to penetrate the center of the main body 51a. And an inlet 51c.

The housing part 54 is formed in a cylindrical shape with both ends open, a casing part 56 is fitted inside the housing part 54, a first hollow part 54 a in which the fixed scroll 51 and the orbiting scroll 52 are accommodated, the orbiting scroll 52 and the rotating shaft 28. A second hollow portion 54b that supports the large-diameter portion 64 that constitutes the driven crank mechanism, and a third hollow portion 54c that supports the rotary shaft 28.
A discharge port 53 that communicates the inner space of the first hollow portion 54a (the discharge side space of the scroll) and the external space is formed along the radial direction of the rotary shaft 28 on the pump 25A side of the first hollow portion 54a. Has been.

The casing portion 56 is integrally provided with the fixed scroll 51 on the inner side and the outer side is fitted with the cylindrical portion 56a fitted inside the first hollow portion 54a, and the working fluid introduction chamber communicated with the introduction port 51c of the fixed scroll 51. 56b, and a suction port 55 that communicates the working fluid introduction chamber 56b and the outer space of the casing portion 56 is formed along the radial direction of the rotary shaft 28.
Here, the discharge port 53 and the suction port 55 are provided substantially parallel to each other, extending in the same angular direction from the axis of the rotary shaft 28, and arranged side by side in the axial direction of the rotary shaft 28.

One end of a pipe whose one end is connected to the outlet of the evaporator 22 is connected to the suction port 55, and the working fluid heated by the evaporator 22 is introduced into the expander 23 through the suction port 55. .
The working fluid introduced into the suction port 55 flows into the working fluid introduction chamber 56b and is then introduced into the center portion of the fixed scroll 51 through the introduction port 51c.
The working fluid introduced into the center of the fixed scroll 51 pushes the wall surface of the orbiting scroll 52 to form an expansion chamber, and the working fluid is continuously supplied to move the expansion chamber to the outer peripheral side. This causes a swivel motion.

One end of a pipe whose one end is connected to the inlet of the condenser 24 is connected to the discharge port 53, and the working fluid that has passed through the expander 23 is sent to the condenser 24 and condensed (liquefied).
The orbiting scroll 52 includes a disk-shaped main body 52a and a scroll portion (spiral body) 52b that is provided in a rib shape on one end surface of the main body 52a.

Here, a rotation prevention mechanism 60 is provided between the surface opposite to the end surface of the main body portion 52a where the scroll portion 52b is formed and the step portion 54d from the first hollow portion 54a to the second hollow portion 54b of the housing portion 54. The orbiting scroll 52 performs the orbiting motion with the expansion of the working fluid while the rotation preventing mechanism 60 prevents the rotation.
As the rotation prevention mechanism 60, there are Oldham coupling, pin & ring coupling, ball coupling, and the like. Here, ball coupling is used, and in particular, ball coupling called EM coupling is used. (Refer to NTN TECHNICICAL REVIEW No. 68 (2000) “EM coupling for scroll compressor”). The EM coupling is composed of two plates and a steel ball obtained by integrally press-molding a race and a ring.

A cylindrical portion 52c is formed to protrude from the end surface of the main body 52a of the orbiting scroll 52 on the side of the rotation prevention mechanism 60, and a drive bearing 61 is provided inside the cylindrical portion 52c. An eccentric bush 62 is fitted to the drive bearing 61, and a crank pin hole 62 a is formed in the eccentric bush 62.
On the other hand, a large-diameter portion 64 is rotatably supported by the second hollow portion 54 b of the housing portion 54 via a bearing 63, and the large-diameter portion 64 is parallel to the rotary shaft 28 and with respect to the rotary shaft 28. The crank pin 64 a is erected by shifting the shaft center, and the crank pin 64 a is inserted into the crank pin hole 62 a of the eccentric bush 62.

The rotary shaft 28 is connected to the large diameter portion 64, and the turning motion around the rotary shaft 28 of the orbiting scroll 52 is rotated by the driven crank mechanism including the eccentric bush 62, the crank pin 64 a, and the large diameter portion 64. Transmit as driving force.
Further, a counterweight (balance weight) 74 for suppressing the occurrence of vibration of the expander 23 is attached to the eccentric bush 62.

Further, in order to restrict the turning radius of the orbiting scroll 52, a restriction hole 64b is provided in the large diameter portion 64, and a restriction projection 62b that fits into the restriction hole 64b is provided in the eccentric bush 62. Oscillation of the eccentric bush 62 around the crank pin 64a is restricted by the engagement between the hole 64b and the restricting protrusion 62b.
The rotary shaft 28 is supported by a bearing 65 provided in the third hollow portion 54 c of the housing portion 54 and is supported by a bearing 67 provided at an end portion of a pump housing 66 connected to the housing portion 54 to rotate.

The pump housing 66 is provided with a pump 25A. The pump 25A is a gear pump as an example, and the gear pump is driven and supported by a drive gear (rotary body) supported on the rotary shaft 28, a driven shaft rotatably supported in parallel with the rotary shaft 28, and the driven shaft. And a driven gear meshing with the gear.
The pump housing 66 is formed with a pump suction port 66a communicating with the suction port of the pump 25A and a pump discharge port 66b communicating with the discharge port of the pump 25A.

One end of a pipe whose one end is connected to the outlet of the condenser 24 is connected to the pump suction port 66a, and the working fluid condensed (liquefied) by the condenser 24 is sucked into the pump 25A. The pump discharge port 66b is connected to the other end of a pipe whose one end is connected to the inlet of the evaporator 22, and the working fluid condensed (liquefied) by the condenser 24 is pumped to the evaporator 22 so that the working fluid is Is evaporated (vaporized).
In addition, a well-known pump can be employ | adopted suitably as the pump 25A, A vane pump etc. other than a gear pump can be used.
A pulley 31 and an electromagnetic clutch 34 that constitute the transmission mechanism 3 are arranged at the end of the rotary shaft 28 that extends through the pump housing 66 to the outside.

A cylindrical portion 66c that encloses the rotary shaft 28 is integrally formed on the end surface of the pump housing 66 opposite to the expander 23 side. A bearing 67 that supports the rotary shaft 28 is disposed on the inner tip side of the tubular portion 66c, and a shaft seal 68 is disposed on the bottom side (expansion device 23 side) of the tubular portion 66c.
And the clutch board 71 is attached to the front-end | tip of the rotating shaft 28 protruded from the cylindrical part 66c, and the pulley 31 is rotatably attached to the outer periphery of the cylindrical part 66c via the bearing 72.

Furthermore, a clutch coil 73 is accommodated in an annular groove 31a formed on the end face of the pulley 31 on the expander 23 side and centering on the rotary shaft 28. The electromagnetic clutch 34 includes the clutch plate 71 and the clutch coil 73 described above. Consists of.
When the clutch coil 73 is energized, a magnetic attractive force is generated, so that the clutch plate 71 comes into contact with the pulley 31 and the pulley 31 and the clutch plate 71 (rotary shaft 28) are interlocked. Power is transmitted between the rotary shaft 28 of the body expander 29A and the engine 10 (crankshaft 10a).

The expander 23 of the pump-integrated expander 29 </ b> A further supplies the working fluid sucked from the suction port 55 to the drive unit (scroll unit) including the fixed scroll 51 and the orbiting scroll 52, and the rotation preventing mechanism 60. A bypass part 80 is provided for bypassing the moving part and leading to the discharge port 53.
The bypass part 80 includes a holder 82 in which a bypass path 81 is formed, and a valve mechanism (electromagnetic valve) 83 that is supported by the holder 82 and opens and closes the bypass path 81, and includes a suction port 55. 56 and a housing portion 54 having a discharge port 53.

Below, the detail of the bypass part 80 is demonstrated, referring FIG.
The holder 82 includes a distal end portion 82 a where the bypass path 81 is formed and a proximal end portion 82 b that holds a coil of the valve mechanism 83. The distal end portion 82 a is in the axial direction of the rotary shaft 28 and the casing portion 56 and the housing. It is clamped between the parts 54.
An accommodation space 91 is provided between the portion of the casing portion 56 where the suction port 55 is formed and the portion of the housing portion 54 where the discharge port 53 is formed. The housing space 91 is a space that is surrounded by the casing portion 56 and the housing portion 54 and that is open toward the outside in the radial direction of the rotating shaft 28.

A suction side communication passage 92 communicating with the suction port 55 is opened on the surface of the casing portion 56 side that sandwiches the tip end portion 82 a of the holder 82 in the axial direction in the storage space 91, and the tip end portion 82 a is pivoted in the storage space 91. A discharge-side communication passage 93 communicating with the discharge port 53 is opened on the surface on the housing part 54 side sandwiched in the direction.
A bypass path 81 extending in the axial direction of the rotary shaft 28 is formed at the distal end portion 82 a of the holder 82, and the distal end portion 82 a is sandwiched between the casing portion 56 and the housing portion 54 in the axial direction of the rotary shaft 28. In this state, one end of the bypass passage 81 is connected to the suction-side communication passage 92, and the other end of the bypass passage 81 is connected to the discharge-side communication passage 93, thereby forming a bypass conduit for the working fluid.

Thus, the bypass portion 80 (holder 82) is disposed between the suction port 55 and the discharge port 53, and directly communicates the suction port 55 and the discharge port 53 with the bypass passage 81 formed in the holder 82. Let In other words, the bypass path 81 formed in the holder 82 is a communication path that extends along the axial direction of the rotary shaft 28 and directly communicates the suction port 55 and the discharge port 53.
The portion of the holder 82 where the end portion on the casing portion 56 side of the bypass path 81 opens forms a cylindrical protrusion 82 c that is formed in a cylindrical shape along a direction parallel to the axis of the rotary shaft 28. A bypass path 81 extends in the axial center portion of the protrusion 82c.

On the other hand, the suction side communication passage 92 has a fitting hole (a diameter-enlarged portion) 92a having a diameter into which the cylindrical projection 82c is fitted and inserted on the holder 82 side (housing portion 54 side). That is, the suction side communication path 92 is formed with a diameter substantially equal to that of the bypass path 81 from the suction port 55 side, and is expanded to a diameter in which the outer periphery of the cylindrical protrusion 82c is fitted.
An annular groove 82f is formed on the outer periphery of the cylindrical protrusion 82c, and a seal member (O-ring) 94 formed in an annular shape by an elastic material such as rubber is fitted into the annular groove 82f. When 82c is fitted into the fitting hole 92a, the gap between the outer periphery of the cylindrical projection 82c and the inner periphery of the fitting hole 92a of the suction side communication path 92 is sealed by the seal member 94.

That is, by fitting the cylindrical protrusion 82 c into the fitting hole 92 a of the suction side communication path 92, the bypass path 81 communicates with the suction port 55 and the position of the holder 82 in the radial direction of the rotary shaft 28 is set. Positioned with reference to the suction side communication path 92, the cylindrical port portion 82 c of the holder 82 and the fitting hole portion 92 a of the casing portion 56, in other words, the suction port 55 side of the bypass path 81 is sealed by a cylindrical seal. Sealed.
The holder 82 and the casing portion 56 abut each other in the axial direction of the rotary shaft 28 between the flat portion 82e at the base portion of the cylindrical protrusion 82c and the flat portion 56c where the suction side communication passage 92 of the casing portion 56 opens. Done in And between the holder 82 and the casing part 56, and between the housing part 54 and the casing part 56, the shim 96 which is metal clamping plates, for example is pinched | interposed, and a rotating shaft is carried out by this shim. The clearance between the fixed scroll 51 and the orbiting scroll 52 in the axial direction 28 is adjusted.

In addition, a pedestal portion 82g that forms an abutting surface parallel to the transverse section of the rotating shaft 28 protrudes from the portion of the holder 82 where the end portion of the bypass path 81 on the housing portion 54 side opens, while the housing portion 54 is formed with a recessed portion 54e having a bottom surface (planar portion) parallel to the end surface (planar portion) of the pedestal portion 82g and having an opening of the discharge side communication passage 93. It is.
When the holder 82 is sandwiched between the housing portion 54 and the casing portion 56 and the pedestal portion 82g is loosely fitted into the recessed portion 54e, the bypass path 81 on the holder 82 side and the discharge side on the housing portion 54 side The communication path 93 is continuous, and the bypass path 81 is connected to the discharge port 53 via the discharge side communication path 93.

In other words, the bypass path 81 is formed from the tip of the cylindrical protrusion 82 c to the pedestal portion 82 g (planar portion), and the holder 82 is sandwiched between the housing portion 54 and the casing portion 56, whereby the suction port 55. And the discharge port 53 communicate with each other by a bypass path 81.
An annular groove 54f is formed on the bottom surface of the recessed portion 54e so as to surround the opening of the discharge side communication passage 93, and a seal member 95 made of an elastic material such as rubber is fitted into the groove 54f. The sealing member 95 is sealed so as to surround the contact surface between the holder 82 and the housing portion 54. That is, the periphery of the connection portion between the bypass path 81 on the holder 82 side and the discharge side communication passage 93 on the housing portion 54 side is sealed with a flat seal. In other words, the bypass passage 81 and the discharge port 53 are sealed with a flat seal.

The seal member 95 is crushed by the holder 82 to generate a force that urges the holder 82 toward the casing portion 56, whereby the holder 82 abuts against the casing portion 56 and the holder 82 rotates. The position of the shaft 28 in the axial direction is positioned with reference to the casing portion 56.
The holder 82 of the bypass unit 80 is integrally provided with a valve mechanism (pilot electromagnetic valve) 83 that is an electromagnetic valve that opens and closes the bypass path 81.

The bypass path 81 includes a pipe line 81a that extends in parallel to the axial direction of the rotary shaft 28 from the casing part 56 side, and a pipe line 81b that extends in parallel to the axial direction of the rotary shaft 28 from the housing part 54 side. Is formed at a position farther from the rotary shaft 28 than the pipe 81b, and the pipes 81a and 81b communicate with each other through a pipe 81c extending in the radial direction of the rotary shaft 28.
In the pipe line 81c, there is a seat part 81d for closing the pipe line 81c (bypass path 81) in the seated state, with the valve body 83a moving and seating from the outside in the radial direction of the rotary shaft 28 to the inside. The plunger 83b is supported so as to be displaceable along the radial direction outside the seat portion 81d in the radial direction.

The plunger 83b is urged toward the seat portion 81d by the coil spring (elastic body) 83c (in a direction approaching the rotation shaft 28) and resists the urging force of the coil spring 83c by the magnetic force of the coil (solenoid) 83d. Thus, it is displaced in a direction away from the sheet portion 81d (rotating shaft 28).
Here, the base end portion 82b of the holder 82 that accommodates the coil 83d is exposed to the outside of the casing portion 56 and the housing portion 54, and a terminal (not shown) for energizing the coil 83d is exposed to the outside. (Omitted) is provided.

A valve body 83a is supported between the plunger 83b and the seat portion 81d so as to be displaceable in the same direction as the advance / retreat direction of the plunger 83b (the radial direction of the rotary shaft 28).
The valve body 83a is formed with a pilot path 83e penetrating in the displacement direction of the valve body 83a, and a pilot valve 83f for closing the opening of the pilot path 83e on the plunger 83b side is formed at the tip of the plunger 83b. ing.

  In the non-energized state of the coil 83d, the plunger 83b is displaced toward the seat portion 81d by the biasing force of the coil spring 83c, so that the valve body 83a is seated on the seat portion 81d by being pushed by the plunger 83b, and The opening on the plunger 83b side of the pilot path 83e is closed by the pilot valve 83f, so that the flow of the working fluid through the bypass path 81 is blocked.

When the coil 83d is energized from the closed state, the plunger 83b is separated from the valve body 83a seated on the seat portion 81d by the magnetic force of the coil 83d, so that the pilot valve 83f is opened from the opening on the plunger 83b side of the pilot path 83e. The pilot path 83e is released and the pilot path 83e is opened.
When the pilot passage 83e is opened, the pressure in the space (main valve chamber) sandwiched between the valve body 83a and the plunger 83b is reduced to the pressure on the discharge port 53 side, while the lower outer side of the valve body 83a. Then, the high pressure on the suction port 55 side acts, and the valve body 83a lifts away from the seat portion 81d due to the pressure difference, and the valve 83 is opened, and the working fluid flows through the bypass path 81, and the coil 83d is energized. While the operation is continued, the valve open state is maintained.

When the energization to the coil 83d is interrupted from the valve open state (energized state), the plunger 83b is displaced in the direction approaching the seat portion 81d by the biasing force of the coil spring 83c, the pilot path 83e is closed, and the plunger 83b is further closed. The valve body 83a is displaced in a direction approaching the seat portion 81d by being pushed, the valve body 83a is seated on the seat portion 81d and returns to the valve closed state, and the valve 83 is closed while the coil 83d is continuously de-energized. Hold.
Thus, the valve mechanism 83 that opens and closes the bypass passage 81 is a so-called pilot-type electromagnetic valve that includes the valve body 83a, the plunger 83b, the coil spring 83c, the coil 83d, and the like.
The valve mechanism 83 is not limited to a pilot-type electromagnetic valve that drives a valve body using a pressure difference between fluids, and is a direct-acting electromagnetic valve that mechanically opens and closes the valve body by driving a movable core. can do.

For example, immediately after the start of the Rankine cycle device 2A with the electromagnetic clutch 34 engaged, the control unit 4 energizes the coil 83d to open the valve mechanism 83, and the intake port 55 and the discharge port 53 are connected. When communicating with the bypass path 81, a bypass path is opened in which the working fluid that has flowed into the expander 23 from the suction port 55 is directly led to the discharge port 53 via the bypass path 81 and discharged to the outside of the expander 23. The working fluid is circulated by bypassing the sliding portions such as the scrolls 51 and 52 as drive units and the rotation preventing mechanism 60 and the drive bearing 61 of the orbiting scroll 52.
As described above, since the bypass path formed by the bypass path 81 has no sliding portions such as the rotation prevention mechanism 60 and the drive bearing 61 of the orbiting scroll 52, the gas-liquid mixed state is obtained when the bypass path 81 is opened. Or even if the working fluid in a liquid phase is circulated, the outflow of the lubricating oil in the sliding portion can be suppressed, and the lubricity of the sliding portion can be sufficiently maintained.

Although the orientation of the suction port 55 and the discharge port 53 in the installed state of the pump-integrated expander 29A (expander 23) is not limited, the direction of sliding when the bypass passage 81 is open is not limited. It is preferable to set the direction so that the outflow of the lubricating oil from the moving part can be suppressed as much as possible. Specifically, the pump-integrated expander 29A (expander 23) is arranged so that the axes of the suction port 55 and the discharge port 53 become horizontal or descending from the inner side to the outer side in the radial direction of the rotary shaft 28. By installing, the outflow of the lubricating oil from the sliding portion, in other words, the flow of the liquid phase working fluid into the sliding portion can be effectively suppressed. In particular, if the suction port 55 and the discharge port 53 are installed so that the axes of the rotary shaft 28 are vertically downward from the inner side to the outer side in the radial direction, the working fluid in the liquid phase is separated from the bypass path. Can be made as small as possible.
Moreover, since the expander 23 is integrally provided with a bypass path 81 and a valve mechanism 83 that opens and closes the bypass path 81, a bypass path having a valve mechanism is connected to a pipe for circulating a working fluid. Compared with the case where it does, the circulation circuit of the working fluid in Rankine cycle device 2A can be simplified.

In addition, a holder 82 (bypass portion 80) having a bypass passage 81 and integrally including a valve mechanism 83 is connected to a casing portion 56 in which a suction port 55 is formed, and a housing portion 54 in which a discharge port 53 is formed. Therefore, the bypass path 81 and the valve mechanism 83 can be provided with a simple structure with respect to the expander 23 (fluid machine), the processing of the expander 23 is simplified, and the shaft of the expander 23 is provided. Expansion of the direction length can be suppressed.
Further, in the valve mechanism 83, the movement direction of the plunger 83b and the valve body 83a is set in the radial direction of the rotary shaft 28. Therefore, the movement space of the plunger 83b and the valve body 83a is long in the radial direction of the rotary shaft 28 and moves. Compared with the case where the direction is a direction parallel to the rotation shaft 28, the axial length of the expander 23 can be suppressed.

Furthermore, since the coil (solenoid) 83d of the valve mechanism 83 is accommodated in the base end portion 82b of the holder 82 exposed to the outside of the casing portion 56 and the housing portion 54, heat can be efficiently radiated from the coil 83d. it can.
In addition, since the coil (solenoid) 83d, which is a large component among the components constituting the valve mechanism 83, is arranged outside the portion sandwiched between the casing portion 56 and the housing portion 54, the coil (solenoid) 83d There is no need to secure the accommodation space in a portion sandwiched between the casing portion 56 and the housing portion 54, and the axial length of the expander 23 can also be suppressed by this.
Further, in the structure in which the holder 82 (bypass portion 80) is sandwiched between the casing portion 56 and the housing portion 54, one connection portion of the bypass path 81 is a cylindrical seal, and the other connection portion is a planar seal. The holder 82 (bypass portion 80) can be easily positioned while blocking the leakage path of the working fluid.

Although the contents of the present invention have been specifically described with reference to the preferred embodiments, it is obvious that those skilled in the art can take various modifications based on the basic technical idea and teachings of the present invention. It is.
For example, the expander 23 shown in FIG. 2 is integrally provided with the pump 25A. However, instead of the pump 25A or together with the pump 25A, a generator can be integrally provided with the expander 23. The above bypass structure can also be applied to an expander that does not include a generator.
The expander 23 may be a rotary expander provided with a rotary piston as a drive unit in addition to the scroll type.

Further, the cylindrical projection 82c of the holder 82 is provided on the surface facing the housing portion 54, the cylindrical projection 82c is fitted into the discharge side communication passage 93, and the pedestal portion 82g of the holder 82 is connected to the casing portion. The base portion 82g can be abutted against the surface of the casing portion 56 where the suction side communication passage 92 is opened. In other words, the connecting portion on the housing portion 54 side of the bypass passage 81 can be sealed with a cylindrical seal, and the connecting portion on the casing portion 56 side of the bypass passage 81 can be sealed with a flat seal.
Further, the extending direction of the suction port 55 and the discharge port 53 is not limited to the radial direction of the rotation shaft 28, and for example, the suction port 55 can be configured to extend in the axial direction of the rotation shaft 28.

In addition to the configuration in which the suction port 55 and the discharge port 53 are in direct communication, the bypass path 81 connects, for example, the working fluid introduction chamber 56b and the discharge port 53, or discharges the suction port 55 or the working fluid introduction chamber 56b. The discharge side space immediately before the port 53 can be connected. That is, the bypass path 81 can be variously modified within a range in which a bypass path that does not pass through sliding portions such as the rotation prevention mechanism 60 and the drive bearing 61 of the orbiting scroll 52 is formed.
Further, the fluid machine is not limited to the expander 23, and may be a compressor.
Furthermore, fluid machines, such as the expander 23, are not limited to what is integrated in a waste-heat utilization apparatus (Rankine cycle apparatus).

  DESCRIPTION OF SYMBOLS 1A ... Waste heat utilization apparatus, 2A ... Rankine cycle apparatus, 10 ... Engine, 21 ... Circulation path, 22 ... Evaporator, 23 ... Expander, 24 ... Condenser, 25A ... Pump, 28 ... Rotating shaft, 29A ... One pump Body expander (fluid machine), 31 ... pulley, 34 ... electromagnetic clutch, 51 ... fixed scroll, 52 ... orbiting scroll, 53 ... discharge port, 54 ... housing part, 55 ... suction port, 56 ... casing part, 60 ... spinning Blocking mechanism 62 ... Eccentric bush 80 ... Bypass part 81 ... Bypass path (communication path) 82 ... Holder, 82c ... Cylindrical protrusion, 83 ... Valve mechanism, 83a ... Valve body, 83b ... Plunger, 83c ... Coil spring , 83d ... Coil 83d, 92 ... Suction side communication path, 92a ... Fitting hole (expanded diameter part), 93 ... Discharge side communication path

Claims (6)

A suction port into which the working fluid that has become high-pressure heating steam flows,
A drive unit driven by expansion of the working fluid sucked from the suction port;
A fluid machine having a discharge port through which the working fluid that has passed through the drive unit and has a low pressure flows out,
A bypass path that guides the working fluid sucked from the suction port to the discharge port by bypassing the sliding part and the drive part of the fluid machine, and the bypass path directly connects the suction port and the discharge port; A fluid machine that communicates. The suction port and the discharge port extend in the radial direction of the rotary shaft of the drive unit, and are provided side by side in the axial direction of the rotary shaft,
The fluid machine according to claim 1, wherein the bypass passage extends in an axial direction of a rotation shaft of the drive unit to directly communicate the suction port and the discharge port . A suction port into which the working fluid that has become high-pressure heating steam flows,
A drive unit driven by expansion of the working fluid sucked from the suction port;
A fluid machine having a discharge port through which the working fluid that has passed through the drive unit and has a low pressure flows out,
The suction port and the discharge port extend in the radial direction of the rotary shaft of the drive unit, and are provided side by side in the axial direction of the rotary shaft,
A bypass path that communicates the suction port and the discharge port, bypasses the sliding portion and the drive section of the fluid machine, and guides the working fluid sucked from the suction port to the discharge port; and the bypass path And a valve mechanism that opens and closes,
The said valve mechanism is a fluid machine which opens and closes the said bypass path by displacing a valve body to the radial direction of the rotating shaft of the said drive part . The fluid machine according to claim 3 , wherein the bypass path is a communication path that directly connects the suction port and the discharge port .   5. The fluid machine according to claim 1, wherein the fluid machine includes a scroll unit including a fixed scroll and a movable scroll as the drive unit, and includes a rotation prevention mechanism that prevents rotation of the movable scroll as the sliding unit. The fluid machine according to any one of the above.   The fluid machine according to claim 5, wherein the fluid machine is a scroll type expander and is incorporated in a Rankine cycle device that collects and uses waste heat of a vehicle engine.