JP2018066297A - Stirling engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stirling engine capable of preventing the entry of lubricating oil into an operation space.SOLUTION: A stirling engine 1 includes a piston 4 to be reciprocated in a cylinder 2, a heat exchanger 7 for promoting the shrinkage and expansion of working fluid in the cylinder 2, and an output takeout device 11 for converting the reciprocating power of the piston 4 into rotating power. The output takeout device 11 is installed in a crank box 50 packaged in a crankcase 13. In the crankcase 13, a first buffer space 17b outside the crank box 50 and a second buffer space 17c inside the crank box 50 are formed. The first and second buffer spaces 17b, 17c are communicated with each other via a breather 32.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a Stirling engine that is an external combustion engine.

  Conventionally, a Stirling engine or the like is known as an external combustion engine that outputs power by contraction and expansion of a working fluid based on a temperature difference caused by heat from the outside. The Stirling engine alternately moves the working fluid between the compression space and the expansion space and repeats the expansion and contraction of the working fluid by the heat exchanger, thereby driving the piston and using the heat from the outside as power. Conversion is performed (see Patent Documents 1 and 2). In such a Stirling engine, the compression type and the expansion space are configured in separate cylinders, the alpha type, the displacer piston and the power piston are both accommodated in the same cylinder, and the displacer piston and the power piston are accommodated in separate cylinders. The gamma type is known.

  Further, the Stirling engine includes an output extraction device such as a crank mechanism that converts the reciprocating motion of the power piston into a rotational motion, and outputs rotational power to the outside. The Stirling engine of the cited document 1 is provided with an output take-out device by a crosshead mechanism below the piston, a cylinder (working space) in which a displacer piston and a power piston are installed, and a crank chamber in which a crankshaft of the crank mechanism is pivotally supported. (Buffer space) is divided into upper and lower parts in the same case. In the Stirling engine of the cited document 2, an output extraction device by a Scotch-yoke mechanism is disposed in a crankcase (buffer space) below a cylinder (working space) in which a displacer piston and a power piston are provided.

JP-A 63-243574 Japanese Patent No. 4873647

  The Stirling engine of Patent Document 1 employs a wet lubrication system that supplies lubricating oil to sliding parts such as bearings. The Stirling engine of Patent Document 2 uses a grease-filled part or an oil-impregnated part for the sliding part. The oil-free lubrication method is used. In the case of the wet lubrication method in Patent Document 1, splashing of lubricating oil in the buffer space may enter the working space, which may cause clogging in a heat exchanger that exchanges heat with the working fluid. On the other hand, in the case of the oil-free lubrication method in Patent Document 2, when the output is increased, it is necessary to increase the load resistance in the sliding portion such as the bearing. It becomes large and it is difficult to downsize the entire engine.

  This invention makes it a technical subject to provide the Stirling engine which considered the above present conditions and improved.

  The present invention includes a piston that reciprocates in a cylinder, a heat exchanger that promotes contraction and expansion of the working fluid in the cylinder, and an output extraction device that converts reciprocating power generated by the piston into rotational power. A Stirling engine that reciprocates the piston by alternately repeating contraction and expansion of the working fluid in the cylinder by an exchanger, wherein the output takeout device is installed in a crank box built in a crankcase, A first buffer space outside the crankbox and a second buffer space inside the crankbox are formed in the crankcase, and the first buffer space and the second buffer space communicate with each other via a breather. In addition, an orifice is connected to the box connecting portion that connects the breather and the second buffer space. In which There are formed.

  In the Stirling engine, the breather is divided into a first compartment communicating with the second buffer space and a second compartment communicating with the first buffer space, and the first and second compartments have orifices. The breather is connected to the communication port to be formed, and the breather is installed at a position higher than the oil level of the lubricating oil sealed in the crank box, with the box connecting portion provided at the lowermost portion, The one-minute chamber may have a volume amount larger than the volume change amount due to the reciprocating motion of the piston.

  In the Stirling engine, the first compartment is divided into two or more treatment chambers including a final treatment chamber communicating with the second compartment by a partition plate provided with a communication hole, and other than the final treatment chamber. The total volume of the processing chamber may be greater than or equal to the volume change amount.

  In the Stirling engine, two or more processing chambers other than the final processing chamber may be provided.

  In the Stirling engine, the first compartment has an initial processing chamber that communicates with the box connecting portion, a final processing chamber that communicates with the second compartment, and an initial processing chamber and a partition plate each having a communication hole. The chambers may be divided into intermediate processing chambers between the final processing chambers, and the volumes of the initial processing chamber, the intermediate processing chamber, and the final processing chamber may be half or more of the volume change amount.

  In the Stirling engine, the breather includes a double case in which an inner case connected to the crank box by the box connecting portion is covered by an outer case connected to the crank case by a case connecting portion opened on an outer peripheral side of the box connecting portion. A box structure, wherein the box connecting portion protrudes from the connecting portion between the case connecting portion and the crankcase into the crankcase and is connected to the crankbox, and the inner case is It is good also as what has the communicating port of the said 1st and 2nd compartment in the uppermost part on the opposite side to a box connection part.

  According to the present invention, the crankcase has a double structure in which the crankbox is contained, and the lubricating oil is enclosed in the crankbox so that the lubricating oil is mixed into the buffer space outside the crankbox in the crankcase. Can be prevented. Therefore, it is possible to more reliably prevent the lubricant from entering the working space in the cylinder, and it is possible to suppress failure due to adhesion of the lubricating oil to the working space or the heat exchanger in the cylinder, or driving problems.

  According to the present invention, in the breather installed at a position higher than the oil level of the lubricating oil, since the first compartment has a volume amount larger than the volume change amount due to the reciprocating motion of the piston, the working fluid flowing into the first compartment The lubricating oil can be separated from the fuel and sent to the second compartment. Accordingly, the ingress of the lubricating oil into the first buffer space communicating with the second compartment is suppressed, and the intrusion of the lubricating oil into the working space in the cylinder and the heat exchanger is surely prevented, so that the driving in the Stirling engine can be prevented. Troubles and mechanical damage can be prevented.

  According to the present invention, when the piston moves to the crankcase side and the working fluid in the second buffer space in the crankbox is scavenged, the total volume of the processing chambers other than the final processing chamber in the first compartment is the scavenging of the working fluid. Therefore, the working fluid from the second buffer space tends to stay in the processing chamber before the final processing chamber. Therefore, the lubricating oil mixed in the working fluid is easily separated from the working fluid in the processing chamber upstream of the final processing chamber, the amount of the lubricating oil flowing into the final processing chamber is suppressed, and the operation of flowing into the first buffer space from the breather. Prevents lubricant from entering the fluid.

  According to the present invention, in the first compartment, the partition plate constituting the processing chamber up to the final processing chamber acts as a baffle plate, and the amount of lubricating oil reaching the final processing chamber can be reduced. Further, when the working fluid flows into the first compartment from the second buffer space, the partition plate separates the lubricating oil by passing through the initial processing chamber and the intermediate processing chamber having a volume equal to or larger than the scavenging amount of the working fluid. Thus, the amount of lubricating oil flowing into the final treatment chamber can be sufficiently reduced.

  According to the present invention, the first branch chamber in the inner case functions as a lubricating oil separation chamber that separates the mist-like lubricating oil mixed with the working fluid flowing in from the second buffer space, and the communication port is connected to the box. By providing at a position away from the section, the lubricating oil that has flowed into the first compartment is unlikely to reach the communication port, and mixing of the lubricating oil into the working fluid flowing into the second compartment can be suppressed. Accordingly, it is possible to reliably prevent the lubricant from entering the working space in the cylinder and the heat exchanger, and to prevent driving problems and mechanical damage in the Stirling engine.

It is the schematic which shows the side surface cross section of the Stirling engine in embodiment of this invention. It is the schematic which shows the front cross section of the Stirling engine. It is side surface sectional drawing of the output taking-out apparatus in the Stirling engine. It is explanatory drawing which shows the connection structure with the displacer piston in the output extraction apparatus. It is explanatory drawing which shows the connection structure with the power piston in the same output taking-out apparatus. It is sectional drawing which shows the structure of the 1st example of the breather in the Stirling engine. It is sectional drawing which shows the structure of the 2nd example of the breather. (A) (b) is sectional drawing which shows another structure of the 2nd example of the breather. It is sectional drawing which shows the structure of the 3rd example of the breather. It is sectional drawing which shows the structure of the 4th example of the breather. It is a figure which shows another structure of an oil level meter. It is the schematic for demonstrating the 2nd example of an oil leak detection part. It is a control flow figure at the time of a stop of the Stirling engine. It is the schematic for demonstrating the 3rd example of an oil leak detection part. It is a schematic sectional drawing of the Stirling engine in another embodiment of this invention.

1. Overall Configuration of Stirling Engine Hereinafter, the overall configuration of a Stirling engine equipped with the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram illustrating a side cross-section of a Stirling engine, and FIG. 2 is a schematic diagram illustrating a front cross-section of the Stirling engine. In the following description, a beta type Stirling engine will be described as an example.

  As shown in FIGS. 1 and 2, the Stirling engine 1 includes a displacer piston 3 and a power piston 4 in a cylinder 2 in which a working fluid such as air, helium gas, or hydrogen is sealed. The cylinder 2 has a configuration in which one end is opened and the other end is closed. The displacer piston 3 is disposed on the closed end side, and the power piston 4 is disposed on the open end side. In the cylinder 2, an expansion space 5 is formed between the closed end and the displacer piston 3, and a compression space 6 is formed between the displacer piston 3 and the power piston 4. The expansion space 5 and the compression space 6 in the cylinder 2 are collectively referred to as a working space.

  The Stirling engine 1 is provided with a heat exchanger 7 that raises and lowers the temperature of the working fluid in the working space in the cylinder 2. The heat exchanger 7 includes a heater 8 that communicates with the expansion space 5 and heats the working fluid by heat input from the outside, and a cooler 9 that communicates with the compression space 6 and cools the working fluid by heat radiation to the outside. It has the structure connected through the regenerator 10 which incorporates the matrix which is a porous heat storage material. When the displacer piston 3 moves toward the opening end side of the cylinder 2, the working fluid heated by the heater 8 flows into the expansion space 5, thereby increasing the temperature of the working fluid. On the other hand, when the displacer piston 3 moves toward the closed end portion of the cylinder 2, the working fluid cooled by the cooler 9 flows into the compression space 6, thereby lowering the temperature of the working fluid. Accordingly, the working fluid flows in the forward and reverse directions between the heat exchanger 7 and the working space in the cylinder 2, whereby the internal pressure in the working space of the cylinder 2 changes, and the power piston 4 is urged to reciprocate.

  The heater 8 is composed of, for example, a group of thin tubes and heat collecting fins to increase the heat transfer area with the external heating medium, and the working fluid passing through the inside receives the heat from the heating medium to raise the temperature. To do. Similarly, in order to increase the heat transfer area with the external cooling medium, the cooler 9 is composed of, for example, a group of thin tubes and heat radiating fins, and the working fluid passing through the inside releases heat to the cooling medium to lower the temperature. To do. The regenerator 10 is composed of, for example, a laminate of metal fibers or a wire mesh, an arrangement of working fluid flow paths arranged in a honeycomb shape, or an inclusion of cotton-like metal fibers. Functions as a regenerative heat exchanger. That is, the regenerator 10 stores the heat of the working fluid when the high-temperature working fluid flows from the heater 8 to the cooler 9, while stores the heat when the low-temperature working fluid flows from the cooler 9 to the heater 8. Heat is released to the working fluid.

  The Stirling engine 1 includes, on the opening end side of the cylinder 2, an output take-out device 11 that converts the reciprocating operation of the power piston 4 into a rotating operation and outputs rotational power. The output take-out device 11 supports a crankshaft 12 connected to the displacer piston 3 and the power piston 4 in a crankcase 13. One end side of the crankshaft 12 serves as an output shaft, and is connected to the input shaft 16 of the generator 15 via the flywheel 14 in the crankcase 13. Further, a buffer space (back space of the power piston 4) 17 is formed by the space 17 a on the opening end side of the power piston 4 in the cylinder 2 and the spaces 17 b and 17 c in the crankcase 13.

  The displacer piston 3 and the power piston 4 reciprocate in the cylinder 2 with a predetermined phase difference by being connected to the crankshaft 12 of the output extraction device 11. In the present embodiment, the phase difference in the reciprocating operation of the displacer piston 3 and the power piston 4 is 90 °.

2. Configuration Example of Output Extraction Device The configuration of the output extraction device 11 in the Stirling engine 1 will be described below with reference to FIGS. As shown in FIGS. 1 to 5, the output take-out device 11 is provided in a crank box 50 fixed inside the crankcase 13. The output take-out device 11 reciprocates in accordance with the power piston 4 and the plate 51 c fixed to the crankshaft guide groove (through groove) 51 a of the displacer yoke (reciprocating portion) 51 that reciprocates in accordance with the displacer piston 3. Crank pins 54 to 54 of the crankshaft 12 are respectively connected to plates 52 c and 53 c fixed to crankshaft guide grooves (through grooves) 52 a and 53 a of the power piston yokes 52 and 53 through bearings 57 to 59. The scotch yoke mechanism 56 is engaged.

  As shown in FIGS. 1 to 5, the crankbox 50 is connected and supported in the crankcase 13, is connected to the cylinder 2 inserted in the crankcase 13, and supports the crankshaft 12. The crankcase 13 is inserted with a part of the cylinder 2 and is connected to an insertion portion of the cylinder 2 to cover the entire crank box 50. That is, the output take-out device 11 is installed inside a casing having a double structure with the crankcase 13 and the crankbox 50. The crankshaft 12 passes through the crankbox 50 and is connected to the flywheel 14 in the crankcase 13.

  As shown in FIG. 4, the displacer yoke 51 is provided with a crankshaft guide groove 51 a that is long in the direction (lateral direction) intersecting the axial directions of the crankshaft 12 and the displacer piston 3. Reciprocating guide holes (through holes) 51b are formed in both sides of the displacer yoke 51 across the crankshaft guide groove 51a in the direction along the axial direction of the displacer piston 3 (vertical direction). A guide shaft 60 fixed to the crank box 50 is inserted into the reciprocating guide hole 51b of the displacer yoke 51 through a linear motion bearing 63 such as a rotor rib bushing. One end of the displacer yoke 51 is connected to the other end of the rod 66 connected to the displacer piston 3, and reciprocates in the same direction (vertical direction) as the displacer piston 3 in accordance with the reciprocating motion of the displacer piston 3.

  As shown in FIG. 5, the power piston yoke 52 (53) is provided with a crank shaft guide groove 52a (53a) which is long in the lateral direction at the center thereof, and both sides sandwiching the crank shaft guide groove 52a (53a). A reciprocating guide hole (through hole) 52b (53b) is formed in the vertical direction. A guide shaft 61 (62) fixed to the crank box 50 is inserted into the reciprocating guide hole 52b (53b) of the power piston yoke 52 (53) via a linear motion bearing 64 (65). . The power piston yoke 52 (53) has one end connected to the other end of the bridge 67 connected to the power piston 4, and reciprocates in the vertical direction in accordance with the reciprocating motion of the power piston 4.

  As shown in FIGS. 3 to 5, through holes 4 a and 67 a are provided at the center of the power piston 4 and the bridge 67 in the direction (vertical direction) along the axial direction of the power piston 4, and are connected to the displacer piston 3. The rod 66 is penetrated. The rod 66 is movable relative to the power piston 4 and the bridge 67, and a dynamic seal mechanism (not shown) such as a mechanical seal is formed at the insertion portion of the rod 66 in the power piston 4.

  As shown in FIGS. 2 to 5, the crankshaft 12 includes a crank pin connected via a rod 66 and a displacer yoke 51 between a crank pin 55 and 56 connected via a bridge 67 and power piston yokes 52 and 53. 54 is provided, and the crankpin 54 is attached to the crankpins 55 and 56 having the same phase with a predetermined phase difference (for example, 90 °). A bridge insertion hole 68 into which the bridge 67 is inserted is provided in a portion of the crank box 50 that is connected to the cylinder 2. The bridge insertion hole 68 of the crank box 50 is formed at a connecting portion between the cylinder 2 and the crank box 50, and the bridge 67 is configured such that the cylinder 2 side portion of the bridge 67 is inserted into and removed from the bridge insertion hole 68. Reciprocates according to the power piston 4. In order to reduce the fluctuation of the internal pressure due to the volume change accompanying the reciprocation of the power piston 4 in the third buffer space 17a on the opening end side of the power piston 4 in the cylinder 2, the third buffer space 17a and the first buffer space A communication port 17d is provided between the communication port 17b and the communication port 17b.

  The displacer piston 3 reciprocates with the rotational power of the crankshaft 12, and the working fluid moves back and forth between the expansion space 5 and the compression space 6 to change the internal pressure of the working space. Due to this pressure change, the power piston 4 reciprocates and the reciprocating power is transmitted to the power piston yokes 52 and 53 via the bridge 67. Thereby, the power piston yokes 52 and 53 reciprocate in the vertical direction along the guide shafts 61 and 62, respectively. Then, the reciprocating motion of the power piston yokes 52 and 53 causes the crankshaft 12 to rotate by reciprocating in the lateral direction while rotating the crankpins 55 and 56 respectively in the crankshaft guide grooves 52a and 53a. Therefore, the output take-out device 11 that receives the reciprocating power of the power piston 4 converts it into rotational power by the Scotch-yoke mechanism and outputs it from the crankshaft 12, and rotates the generator 15 via the flywheel 14 and the input shaft 16. Let

  As shown in FIGS. 1 to 5, the Stirling engine 1 of the present embodiment employs a wet lubrication method in which lubricating oil is supplied to the sliding portion of the output take-out device 11. The crank box 50 is configured as an oil tank that stores lubricating oil, and the bridge 67 is inserted into the bridge insertion hole 68 not only in the penetrating portion of the crankshaft 12 but also in the connecting portion between the cylinder 2 and the crank box 50. An oil seal (not shown) is provided at the portion, the portion where the rod 66 is inserted into the through hole 67a, and the like. That is, the crank box 50 has a sealing structure so that the stored lubricating oil does not leak to the outside, and the crank case 13 includes a first buffer space 17b outside the crank box 50 and a first buffer space inside the crank box 50. 2 buffer spaces 17c are formed.

  That is, the crankcase 13 has a double structure in which the crankbox 50 is embedded, and the lubricating oil is mixed into the first buffer space 17b in the crankcase 13 by sealing the lubricating oil in the crankbox 50. Can be prevented. Accordingly, it is possible to more reliably prevent the lubricating oil from entering the third buffer space 17a, that is, the inside of the cylinder 2 from the first buffer space 17b through the communication port 17d, and the working space and the heat exchanger 7 in the cylinder 2 can be prevented. It is possible to suppress malfunctions due to adhesion of lubricating oil to the etc. and driving problems.

  As shown in FIGS. 1 and 3, the first buffer space 17 b in the crankcase 13 communicates with the second buffer space 17 c in the crank box 50 via the breather 32. The breather 32 is fixed to the crankcase 13 at a position above the oil level of the lubricating oil stored in the crank box 50. The breather 32 is divided into a first compartment 35 that communicates with the second buffer space 17c and a second compartment 36 that communicates with the first buffer space 17b. The first compartment 35 and the second compartment 36 communicate with each other. It communicates with the mouth 37.

  With this configuration, the lubricating oil that has entered the breather 32 is separated from the working fluid in the first compartment 35, and only the working fluid flows into the first buffer space 17 b of the crankcase 13 through the second compartment 36. Accordingly, it is possible to reliably prevent the lubricating oil from entering the first buffer space 17b, and it is possible to prevent driving problems and mechanical problems due to clogging caused by the lubricating oil adhering to the working space in the cylinder 2 and the heat exchanger 7 or the like. Damage can be prevented. Moreover, the breather 32 has a configuration in which an orifice is formed by reducing the opening area of the box connecting portion 44 that is connected to the crank box 50, and intrusion of lubricating oil from the crank box 50 can be suppressed. Further, the communication port 37 between the first compartment 35 and the second compartment 36 is also configured by an orifice having a small opening area.

  The breather 32 covers an inner case 71 connected to the crank box 50 by a box connecting portion 44 constituting an orifice by an outer case 72 connected to the crank case 13 by a case connecting portion 38 opened on the outer peripheral side of the box connecting portion 44. It has a double tube structure. The breather 32 has a double opening formed by the case connecting portion 38 and the box connecting portion 44 at the lowermost portion, and is connected to the crankcase 13 and the crank box 50. The box connecting portion 44 protrudes from the connecting portion between the case connecting portion 38 and the crankcase 13 into the crankcase 13 and is connected to the crankbox 50. The inner case 71 has a communication port 37 at the uppermost part opposite to the box connecting portion 44, and the first compartment 35 inside the inner case 71 and the second compartment 36 between the inner case 71 and the outer case 72. Communicate with.

  The inner case 71 (first compartment 35) in the breather 32 is configured such that its volume is larger than the volume change amount in the buffer space 17 due to the reciprocating motion of the power piston 4. The inner case 71 is configured such that the uppermost portion of the inner case 71 provided with the communication port 37 is positioned sufficiently higher than the box connecting portion 44. As a result, when the working fluid including the lubricating oil flows into the first compartment 35 from the second buffer space 17c in the crank box 50 through the box connecting portion 44, the lubricating oil does not reach the communication port 37 and is discharged from the working fluid. Therefore, only the working fluid can flow into the first buffer space 17b in the crankcase 13 through the second compartment 36 and the case connecting portion 38.

  As shown in FIGS. 1 to 3, an oil level gauge 46 is installed outside the crankcase 13 in order to check the amount of lubricating oil in the crankbox 50. Therefore, when the Stirling engine 1 is stopped, the amount of lubricating oil in the crank box 50 inside the crankcase 13 can be confirmed by confirming the oil surface position of the lubricating oil in the oil level gauge 46. At this time, when the oil level position of the oil level gauge 46 is lower than the predetermined position, not only the amount of lubricating oil in the crankbox 50 is insufficient from the necessary minimum amount but also a part of the lubricating oil in the crankbox 50. Can be recognized as leaking into the crankcase 13.

  In addition, as shown in FIGS. 1 to 3, an oil leakage detection unit 47 is provided at the bottom of the bottom 45 of the crankcase 13 in order to detect lubricating oil that has leaked from the crankbox 50 to the crankcase 13. . The bottom 45 of the crankcase 13 is shaped so that the lubricating oil leaked from the crank box 50 flows toward the installation location of the oil leakage detection portion 47 with the installation location of the oil leakage detection portion 47 as the lowermost portion. Have. Thereby, when the Stirling engine 1 is driven, the lubricating oil flowing into the oil leakage detecting unit 47 is detected, and it can be recognized that a part of the lubricating oil in the crank box 50 is leaking into the crankcase 13. .

  As shown in FIGS. 1 to 3, a deformation preventing member 91 that prevents deformation of the power piston yokes 52, 53 and the bridge 67 is installed at a connecting portion between the power piston yokes 52, 53 and the bridge 67. The displacer piston 3, the power piston 4, the displacer yoke 51, the power piston yokes 52 and 53, the rod 66, the bridge 67, and the like have specific gravity in order to reduce the load on each part of the Stirling engine 1 due to the inertial force based on the reciprocating motion. It is made of a light metal material such as light aluminum or a light metal alloy material. On the other hand, the deformation preventing member 91 is made of a metal material such as iron having a higher specific gravity than the metal materials constituting the power piston yokes 52 and 53 and the bridge 67.

  By providing the deformation preventing member 91, the compression space 6 in the cylinder 2 becomes high pressure, and even if the load to the bridge 67 and the power piston yokes 52 and 53 through the power piston 4 becomes large, it is made of a highly rigid material. The deformation preventing member 91 can suppress deformation of the bridge 67 and the power piston yokes 52 and 53. Therefore, it is possible to prevent abnormal wear and peeling (flaking) in the bearings 58 and 59 that are in sliding contact with the crankshaft guide grooves 52a and 53a of the power piston yokes 52 and 53.

  Further, since the displacement of the relative positions of the linear motion bearings 64, 65 with respect to the guide shafts 61, 62 is also suppressed, the gap (clearance) between the guide shafts 61, 62 and the linear motion bearings 64, 65 can be properly maintained. Abnormal wear and separation at the guide shafts 61 and 62 and the linear motion bearings 64 and 65 can be prevented. Furthermore, the deformation preventing member 91 is made of a metal material having a smaller linear expansion coefficient (thermal expansion coefficient) than that of the light metal material or the light metal alloy material, so that thermal deformation in the bridge 67 and the power piston yokes 52 and 53 can be suppressed. .

3-1. First Example of Breather A first example of the breather 32 installed in the output extraction device 11 will be described below with reference to FIG. As shown in FIG. 6, the breather 32 of this example is divided into a first compartment 35 that communicates with the second buffer space 17c and a second compartment 36 that communicates with the first buffer space 17b. The two compartments 35 and 36 communicate with each other through a communication port 37 that forms an orifice. The breather 32 is provided with a box connecting portion 44 at the lowermost portion and is installed at a position higher than the oil level of the lubricating oil sealed in the crank box 50, and the first compartment 35 has a volume change due to the reciprocating motion of the piston. It has a volume that is greater than the amount.

  In the breather 32 installed at a position higher than the oil level of the lubricating oil, since the first compartment 35 has a volume amount larger than the volume change amount due to the reciprocating movement of the piston, lubrication is performed from the working fluid flowing into the first compartment 35. The oil can be separated and sent to the second compartment 36. Therefore, the ingress of the lubricating oil into the first buffer space 17b communicating with the second compartment 36 is suppressed, and the ingress of the lubricating oil into the working space in the cylinder 2 and the heat exchanger 7 is surely prevented. It is possible to prevent driving problems and mechanical damages in 1.

  The breather 32 has a double tube structure in which the inner case 71 connected to the crank box 50 by the box connecting portion 44 is covered by the outer case 72 connected to the crank case 13 by the case connecting portion 38 opened on the outer peripheral side of the box connecting portion 44. have. A box connecting portion 44 projects from the connecting portion between the case connecting portion 38 and the crankcase 13 into the crankcase 13 and is connected to the crankbox 50. The inner case 71 has a communication port 37 for the first and second compartments 35 and 36 at the uppermost portion on the opposite side of the box connecting portion 44.

  With this configuration, the first compartment 35 in the inner case 71 functions as a lubricating oil separation chamber that separates mist-like lubricating oil mixed with the working fluid flowing in from the second buffer space 17c. By providing the communication port 37 at a position away from the box connecting portion 44, the lubricating oil that has flowed into the first compartment 35 is less likely to reach the communication port 37, and the lubricating oil with respect to the working fluid flowing into the second compartment 36 can be prevented. Mixing can be suppressed.

  The first compartment 35 formed in the inner case 71 is divided into the processing chambers 41 and 42 by a partition plate 73 having a communication hole 74. The volume of the initial processing chamber 42 communicating with the second buffer space 17c is equal to or greater than the volume change amount due to the reciprocating motion of the power piston 4. When the power piston 4 moves to the crankcase 13 side and the working fluid in the second buffer space 17c in the crankbox 50 is scavenged, the initial processing chamber 42 of the first compartment 35 of the breather 32 exceeds the scavenging amount of the working fluid. Therefore, the working fluid from the second buffer space 17c tends to stay in the initial processing chamber 42.

  Accordingly, the lubricating oil mixed in the working fluid is easily separated from the working fluid in the initial processing chamber 42, the amount of lubricating oil flowing into the final processing chamber 41 is suppressed, and flows into the first buffer space 17b from the breather 32. Prevents lubricant from entering the working fluid. At this time, the volume of the final processing chamber 41 communicating with the second compartment 36 is set to be half or more of the volume change amount due to the reciprocating motion of the power piston 4, thereby further reducing the inflow amount of the lubricating oil into the second compartment 36. it can.

  An orifice is formed by reducing the opening area of the box connecting portion 44 connected to the crank box 50, and the communication port 37 between the first compartment 35 and the second compartment 36 and the communication hole 74 of the partition plate 73 are also provided. It is constituted by an orifice having a small opening area. At this time, the opening of the case connecting portion 38 and the communication hole 74 are disposed at positions offset from each other, and the communication port 37 and the communication hole 74 are disposed at positions offset from each other, whereby the second compartment 36 is disposed. Intrusion of lubricating oil into is prevented.

  That is, the communication hole 74 and the communication port 37 constitute an orifice, and are arranged in a staggered manner (offset arrangement) along the flow of the working fluid, so that the partition plate 73 and the inner case 71 are arranged in the first compartment 35. , Which serves as a shielding wall for the working fluid flowing from the first to the second compartment 36 and promotes separation of the mixed lubricating oil. Therefore, the working fluid free of lubricant oil can flow into the first buffer space 17b via the breather 32.

3-2. Second Example of Breather Next, a second example of the breather 32 installed in the output extraction device 11 will be described below with reference to FIG. As shown in FIG. 7, the breather 32 of this example includes three processing chambers 41 to 35 including a final processing chamber 41 in which the first compartment 35 communicates with the second compartment 36 by a partition plate 73 having a communication hole 74. It is divided into 43 rooms. The total volume of the processing chambers 42 and 43 other than the final processing chamber 41 is equal to or larger than the volume change amount due to the reciprocating motion of the power piston 4. By configuring in this way, the partition plate 73 constituting the processing chambers 42 and 43 up to the final processing chamber 41 acts as a baffle plate, and the amount of lubricating oil reaching the final processing chamber 41 can be reduced.

  That is, the first compartment 35 is connected to the box connecting portion 44 by the partition plate 73 having the communication holes 74, the final processing chamber 41 that communicates with the second compartment 36, and the initial processing chamber 42. It is divided into an intermediate processing chamber 43 between the final processing chambers 41. The volumes of the initial processing chamber 42, the intermediate processing chamber 43, and the final processing chamber 41 are more than half of the volume change amount due to the reciprocating motion of the power piston 4.

  Thus, when the working fluid flows into the first compartment 35 from the second buffer space 17c, the partition plate 73 passes through the initial processing chamber 42 and the intermediate processing chamber 43 having a volume equal to or larger than the scavenging amount of the working fluid. Thus, the amount of lubricating oil flowing into the final processing chamber 41 can be sufficiently reduced by blocking the lubricating oil. Further, by configuring each of the initial processing chamber 42, the intermediate processing chamber 43, and the final processing chamber 41 with the same volume, it is possible to share the components that constitute each of the processing chambers 41 to 43, and each processing chamber. It can be easily assembled by laminating 41-43.

  Also in this example, the communication hole 74 and the communication port 37 form an orifice, and are arranged in a staggered manner (offset arrangement) along the flow of the working fluid, so that the partition plate 73 and the inner case 71 can be It becomes a shielding wall for the working fluid flowing from the first compartment 35 to the second compartment 36, and promotes separation of the mixed lubricating oil. That is, the opening of the case connecting portion 38 and the communication hole 74 are offset, the communication port 37 and the communication hole 74 in the final processing chamber 41 are offset, and the initial stage of the intermediate processing chamber 43 is further increased. The communication holes 74 of the two partition plates 73 provided on the processing chamber 42 side and the final processing chamber 41 side (upper and lower sides) are offset.

  In addition, the breather 32 of this example is not restricted to the capacity | capacitance of each process chamber 41-43 in the 1st division chamber 35 being equal, but from 2nd buffer space 17c as shown to Fig.8 (a). The interval between the partition plates 73 may be narrowed along the flow of the working fluid toward the one buffer space 17b, and the volume may be reduced in the order of the initial processing chamber 42, the intermediate processing chamber 43, and the final processing chamber 41. At this time, the total volume of the initial processing chamber 42 and the intermediate processing chamber 43 is set to be equal to or larger than the volume change amount due to the reciprocating motion of the power piston 4, thereby reducing the amount of lubricant mixed in the working fluid flowing into the final processing chamber 41. It can be reduced sufficiently.

  In addition, the breather 32 of this example is not limited to the configuration in which the first compartment 35 is separated into three chambers. As shown in FIG. 35 may be divided into four or more rooms. At this time, by setting the total volume of the initial processing chamber 42 and the plurality of intermediate processing chambers 43 to be equal to or greater than the volume change amount due to the reciprocating motion of the power piston 4, the number of partition plates 73 that partition the processing chambers 41 to 43 can be reduced. Therefore, the lubricating oil does not easily reach the final processing chamber 41. Therefore, the amount of lubricating oil mixed into the working fluid flowing into the final processing chamber 41 can be sufficiently reduced, and even if the volume of the final processing chamber 41 is reduced, the inflow of lubricating oil into the first buffer space 17b can be prevented. The breather 32 can be reduced in size.

3-3. Third Example of Breather Next, a third example of the breather 32 installed in the output extraction device 11 will be described below with reference to FIG. As shown in FIG. 9, the breather 32 of this example is provided with a baffle plate 76 (lubricating oil trap) that blocks the inflow of lubricating oil at the opening of the box connecting portion 44 and the communication hole 74 of the partition plate 73. Thereby, when the working fluid from the second buffer space 17c flows into the breather 32, when flowing into the initial processing chamber 42 from the second buffer space 17c, when flowing into the intermediate processing chamber 43 from the initial processing chamber 42, and At each time of inflow from the intermediate processing chamber 43 to the final processing chamber 41, the baffle plate 76 blocks the passage of the lubricating oil.

  Accordingly, since the separation of the lubricating oil can be more reliably promoted by the installation of the baffle plate 76, the volume of the first compartment 35 can be reduced as compared with the first and second examples, and the breather 32 can be configured compactly. can do. In this example, as in the second example, the intermediate processing chamber 43 is provided. However, the intermediate processing chamber 43 may be omitted as in the first example.

3-4. Fourth Example of Breather Next, a fourth example of the breather 32 installed in the output extraction device 11 will be described below with reference to FIG. As shown in FIG. 10, the breather 32 of this example has a filter net 77 at the communication port 37 between the first compartment 35 and the second compartment 36. Thereby, since the working fluid passing through the communication port 37 passes through the filter net 77, the mist-like lubricating oil mixed in the working fluid adheres to the filter net 77 and is separated from the working fluid. Only fluid can flow into the second compartment 36. Note that the filter net 77 in this example may be provided in the opening of the box connecting portion 44 or the communication hole 74 of the partition plate 73.

4). Oil Level Gauge The oil level gauge 46 installed in the output take-out device 11 will be described below with reference to FIG. As shown in FIG. 3, an oil level gauge 46 on the flow paths 81 and 82 connecting both ends to the crank box 50 is provided outside the crank case 13. A lower flow path 81 communicating with the crankbox 50 at a position lower than the oil level of the lubricating oil in the crankbox 50, and an upper side communicating with the crankbox 50 at a position higher than the oil level of the lubricating oil in the crankbox 50. The oil level gauge 46 is connected to the flow path 82.

  A lower port 83 communicating with the lower flow path 81 is provided on the bottom surface of the crank box 50, and the upper flow path 82 is positioned higher than the oil level of the lubricating oil in the side wall erected from the bottom surface of the crank box 50. An upper port 84 that communicates with the upper port 84 is provided. The lower flow path 81 and the upper flow path 82 penetrate the crankcase 13 and are led out to the outside of the crankcase 13 so that the oil level of the lubricating oil in the crank box 50 (the oil level when the Stirling engine 1 is stopped) is visually recognized. It is connected to the oil level gauge 46 to be enabled. Thereby, by visually recognizing the oil level of the lubricating oil in the oil level gauge 46, the oil level of the lubricating oil in the crank box 50 can be confirmed. Therefore, it is possible not only to check the excess or deficiency of the lubricating oil in the crankbox 50 but also to check the leakage of the lubricating oil from the crankbox 50 to the crankcase 13.

  In the crank box 50, a baffle plate 85 is provided at a portion communicating with the upper flow path 82. That is, the baffle plate 85 extends from the side wall of the crank box 50 so as to cover the upper port 84 from below the upper port 84. Thereby, the lubricating oil stirred during the driving of the Stirling engine 1 is prevented from entering the oil level gauge 46 through the upper flow path 82. Accordingly, it is possible to prevent the lubricating oil from flowing back to the oil level gauge 46 through the upper flow path 82, and to prevent measurement abnormality of the oil level gauge 46 due to, for example, clogging of the pipe line due to adhesion of the lubricating oil in the upper flow path 82. The oil level position in the crankbox 50 can be normally measured.

  In the present embodiment, the baffle plate 85 is provided in the crank box 50 to prevent the mist-like lubricating oil from entering the upper flow path 82. However, as shown in FIG. 32 may have a structure in which the upper flow path 82 is communicated with each other. That is, when the upper flow path 82 is communicated with the second compartment 36 of the breather 32, the working fluid that is not mixed with the lubricating oil flows into the upper flow path 82, and the oil due to the intrusion of the lubricating oil into the upper flow path 82. Measurement abnormality of the surface meter 46 can be prevented.

5-1. First Example of Oil Leak Detection Unit A first example of the oil leak detection unit 47 installed in the output extraction device 11 will be described below with reference to FIG. As shown in FIG. 3, the oil leakage detection unit 47 of this example includes an oil storage unit 86 that stores lubricating oil in the crankcase 13, and is provided at the bottom of the bottom 45 of the crankcase 13. . The oil reservoir 86 is configured to be visible from the outside, and the leakage of the lubricant from the crank box 50 can be recognized by confirming the amount of lubricant in the oil reservoir 86. Accordingly, not only the lack of lubricating oil in the crankbox 50 but also the abnormality of each component in the Stirling engine 1 including the deterioration of the oil seal can be detected. Therefore, the Stirling engine 1 can be stopped to prevent the Stirling engine 1 from being damaged. .

5-2. Second Example of Oil Leak Detection Unit Next, a second example of the oil leak detection unit 47 installed in the output extraction device 11 will be described below with reference to FIGS. 12 and 13. As shown in FIG. 12, the oil leakage detection unit 47 of this example includes an oil leakage amount sensor 87 that detects the leakage of lubricating oil to the oil storage unit 86, and the controller 29 Based on this signal, the opening / closing of the pressure equalizing valve 20 and the working space release valve 22 in the operation stop pipe 18 is controlled. The oil leakage amount sensor 87 is constituted by an optical sensor or the like, and measures the amount of lubricating oil in the oil reservoir 86 by measuring the oil level of the lubricating oil in the oil reservoir 86.

  The operation stop pipe 18 is provided with a pressure equalizing valve 20 in a bypass flow path 19 that allows the working space in the cylinder 2 and the buffer space 17 to communicate with each other, and the working space is opened to the atmosphere by communicating with the working space in the cylinder 2. A working space release valve 22 is installed in the flow path 21. The bypass passage 19 communicates the compression space 6 in the cylinder 2 with the first buffer space 17b in the crankcase 13. At this time, the bypass channel 19 is connected to the outer case 72 of the breather 32, thereby communicating with the first buffer space 17 b through the second compartment 36. The working space opening flow path 21 is provided so as to branch from between the pressure equalizing valve 20 and the compression space 6 in the bypass flow path 19.

  As shown in FIG. 13, when the Stirling engine 1 is normally stopped, the controller 29 opens the pressure equalizing valve 20 so that the compression space 6 and the first buffer space 17b are communicated with each other by the bypass passage 19. Thereby, the reciprocating operation of the displacer piston 3 and the power piston 4 is stopped so that the pressure in the working space in the cylinder 2 and the pressure in the buffer space 17 become the same pressure. When the Stirling engine 1 is stopped urgently, the controller 29 first opens the pressure equalizing valve 20 to connect the compression space 6 and the first buffer space 17b through the bypass flow path 19. Thereafter, when the pressure in the compression space 6 and the first buffer space 17b approaches, the controller 29 opens the working space release valve 22 and releases the working fluid in the compression space 6 to the outside through the working space release flow path 21. The reciprocating operation of the displacer piston 3 and the power piston 4 is stopped.

  The oil leakage amount sensor 87 detects the amount of lubricant stored in the oil reservoir 86 and transmits a detection signal to the controller 29. Therefore, the controller 29 can automatically detect abnormality of each component in the Stirling engine including not only lack of lubricating oil in the crank box 50 but also deterioration of the oil seal. The controller 29 urgently stops the Stirling engine 1 when confirming that the amount of lubricating oil in the oil reservoir 86 exceeds a predetermined amount based on the detection signal of the oil leakage amount sensor 87. Therefore, when it is determined that the leakage amount of the lubricating oil from the crankbox 50 is large based on the signal from the oil leakage amount sensor 87, the Stirling engine 1 can be automatically stopped, and the Stirling engine is damaged. Can be prevented.

5-3. Third Example of Oil Leak Detection Unit Next, a third example of the oil leak detection unit 47 installed in the output extraction device 11 will be described below with reference to FIG. As shown in FIG. 14, the oil leakage detection unit 47 of this example includes an oil leakage speed sensor 88 that detects the oil leakage speed of the lubricating oil from the crankcase 13 to the oil storage unit 86. Based on the signal from the oil speed sensor 88, the opening / closing of the pressure equalizing valve 20 and the working space release valve 22 in the operation stop pipe 18 is controlled. The oil leak rate sensor 88 is configured by installing a plurality of oil leak detection sensors 89a and 89b such as optical sensors at different height positions, and stores oil according to the measurement timing of the lubricating oil in the oil leak detection sensors 89a and 89b. The oil leakage rate of the lubricating oil to the part 86 is measured.

  When the controller 29 of this example confirms that the oil leakage speed of the lubricating oil in the oil reservoir 86 is higher than a predetermined speed based on the detection signal of the oil leakage speed sensor 88, the controller 29 first opens the pressure equalizing valve 20. Thus, the compression space 6 and the first buffer space 17 b are communicated by the bypass flow path 19. Thereafter, when the pressure in the compression space 6 and the first buffer space 17b approaches, the controller 29 opens the working space release valve 22 and releases the working fluid in the compression space 6 to the outside through the working space release flow path 21. The reciprocating operation of the displacer piston 3 and the power piston 4 is stopped. Accordingly, when it is determined that the amount of leakage of the lubricating oil from the crankbox 50 is large based on the signal from the oil leakage speed sensor 88, the Stirling engine 1 is automatically emergency stopped and the Stirling engine Damage can be prevented.

(Another embodiment)
The Stirling engine 1 in the above-described embodiment has a configuration in which the output take-out device 11 is provided below the cylinder 2, and the reciprocating motion unit including the displacer piston 3 and the power piston 4 reciprocates in the vertical direction (vertical direction). However, the output take-out device 11 may be provided on the side of the cylinder 2 so that the reciprocating unit including the displacer piston 3 and the power piston 4 reciprocates in the horizontal direction (lateral direction). Below, the Stirling engine 1 of another embodiment which provided the output taking-out apparatus 11 in the cylinder 2 side is demonstrated with reference to FIG.

  As shown in FIG. 15, in the Stirling engine 1 of the present embodiment, a crank box 50 that houses an output take-out device 11 is housed in a crank case 13, and the bottom 45 of the crank case 13 is formed by a displacer piston 3 and a power piston 4. The surface is parallel to the piston axis. Also in the present embodiment, the breather 32 is installed at a position higher than the oil level of the lubricating oil in the crank box 50, and the oil leakage detector 47 is installed at the bottom 45 of the crankcase 13. An oil level gauge 46 is provided outside the crankcase 13, and the lower flow path 81 passes through the bottom 45 of the crankcase 13 and communicates with the lower port 83 on the bottom surface of the crankbox 50, and the upper flow path 82. Passes through the side wall of the crankcase 13 and communicates with the upper opening 84 on the side wall of the crankbox 50.

In addition, the structure of each part in this invention is not limited to embodiment of illustration, A various change is possible in the range which does not deviate from the meaning of this invention. For example, although the above embodiment has been described based on a beta type Stirling engine, other types of Stirling engines such as an alpha type and a gamma type may be used. Further, the output take-out device is not limited to the Scotch / yoke mechanism in the above-described embodiment, and may have another configuration such as a crosshead mechanism.

DESCRIPTION OF SYMBOLS 1 Stirling engine 2 Cylinder 3 Displacer piston 4 Power piston 5 Expansion space 6 Compression space 7 Heat exchanger 11 Output take-out device 12 Crankshaft 13 Crankcase 17 Buffer space 17b First buffer space 17c Second buffer space 32 Breather 35 First compartment 36 Second branch chamber 37 Communication port 38 Case connecting portion 41 Final processing chamber 42 Initial processing chamber 43 Intermediate processing chamber 44 Box connecting portion 45 Bottom portion 46 Oil level gauge 47 Oil leak detecting portion 50 Crank box 71 Inner case 72 Outer case 73 Partition plate 74 Communication hole 76 Baffle plate 77 Filter net 81 Lower flow path 82 Upper flow path 83 Lower port 84 Upper port 85 Baffle plate 86 Leakage storage part 87 Leakage amount sensor 88 Leakage rate sensor 89a Leakage detection sensor 89b Leakage Detection sensor

Claims (6)

A piston that reciprocates in the cylinder; a heat exchanger that promotes contraction and expansion of the working fluid in the cylinder; and an output extraction device that converts reciprocating power generated by the piston into rotational power. A Stirling engine that reciprocates the piston by alternately repeating contraction and expansion of the working fluid in the cylinder,
The output take-out device is installed in a crank box built in a crankcase, and a first buffer space outside the crankbox and a second buffer space inside the crankbox are formed in the crankcase. And
The Stirling engine, wherein the first buffer space and the second buffer space communicate with each other through a breather, and an orifice is formed at a box connecting portion that communicates the breather with the second buffer space. The breather is divided into a first compartment that communicates with the second buffer space and a second compartment that communicates with the first buffer space, and the first and second compartments are communication ports that form orifices. Communicated,
In the breather, the box connecting portion is provided at the lowermost portion, and is installed at a position higher than the oil level of the lubricating oil sealed in the crank box, and the first compartment has a volume change caused by a reciprocating motion of a piston. The Stirling engine according to claim 1, wherein the Stirling engine has a volume amount larger than the amount.   The first compartment is divided into two or more treatment chambers including a final treatment chamber communicating with the second compartment by a partition plate having a communication hole, and a total of the treatment chambers other than the final treatment chamber is divided. The Stirling engine according to claim 2, wherein the volume is equal to or greater than the volume change amount.   The Stirling engine according to claim 3, wherein there are two or more processing chambers other than the final processing chamber.   The first compartment has a partition plate provided with a communication hole, an initial processing chamber communicating with the box connecting portion, a final processing chamber communicating with the second compartment, and between the initial processing chamber and the final processing chamber. The volume of each of the initial processing chamber, the intermediate processing chamber, and the final processing chamber is half or more of the volume change amount. Stirling engine. The breather has a double tube structure in which an inner case connected to the crank box by the box connecting portion is covered by an outer case connected to the crank case by a case connecting portion opened on an outer peripheral side of the box connecting portion. ,
The box connecting portion is protruded from the connecting portion between the case connecting portion and the crankcase to the inside of the crankcase, and is connected to the crankbox,
The Stirling according to any one of claims 2 to 5, wherein the inner case has a communication port for the first and second compartments at an uppermost portion opposite to the box connecting portion. engine.

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