JP2021025418A - β type Stirling engine - Google Patents

Abstract

To provide a β type Stirling engine capable of reducing costs.SOLUTION: A Stirling engine comprises: a crank case 13 formed in a cross shape with a first cylindrical part 131 including a reciprocating power piston and a second cylindrical part 132 including a crank shaft capable of being rotated by the reciprocating movement of the power piston intersecting with each other; and a frame 18 for installing the crank case 13 in an operating place. The frame 18 is integrally formed with the crank case 13.SELECTED DRAWING: Figure 4

Description

The present invention relates to a β-type Stirling engine.

A β-type Stirling engine in which a displacer piston and a power piston are housed in the same cylinder is known (for example, Patent Document 1 below). When the Stirling engine is installed in the operating location, the crankcase is attached to the operating location via the frame, but the crankcase and the frame are separate parts. This is because the roles and functions of the crankcase and the frame are different, and there is an advantage that the structure can be changed relatively easily if the crankcase and the frame have different configurations.

However, in the conventional structure, since the crankcase and the frame are separate parts, it is necessary to consider the assembly for connecting the two parts, and the frame has to be composed of a plurality of parts. Therefore, the number of parts is large. It was in a disadvantageous state in terms of cost, such as an increase in cost, an increase in cost, and an increase in assembly cost.

Japanese Unexamined Patent Publication No. 62-20396

Therefore, in view of the above problems, an object of the present invention is to provide a β-type Stirling engine capable of reducing costs.

In the β-type Stirling engine of the present invention, a first cylindrical portion containing a reciprocating piston and a second cylindrical portion containing a crankshaft rotatable by the reciprocating movement of the piston intersect to form a cross. With the formed crankcase,
A frame for installing the crankcase in an operating place is provided.
The frame is integrally formed with the crankcase.

Further, in the β-type Stirling engine of the present invention, the frame is formed symmetrically with respect to a virtual central plane including the central axis of the first cylindrical portion and the central axis of the second cylindrical portion. It may have an end face and a second end face.

Further, in the β-type Stirling engine of the present invention, the frame may have a flat third end surface orthogonal to the central axis of the first cylindrical portion.

Further, in the β-type Stirling engine of the present invention, the frame is formed between the tip of the first cylindrical portion in the protruding direction and the middle portion of the protruding portion protruding from the second cylindrical portion, and the second cylindrical portion. Of the cylindrical portions of the above, the one protruding from the first cylindrical portion may be coupled to the crankcase between the tip portion in the protruding direction and the intermediate portion.

Further, in the β-type Stirling engine of the present invention, the frame has a square tubular shape.
The four plate members constituting the square cylinder are formed from two projecting portions of the first cylindrical portion protruding from the second cylindrical portion and from the first cylindrical portion of the second cylindrical portion. It may be coupled to each of the two protruding portions.

According to the present invention, by forming the frame integrally with the crankcase, it is possible to reduce the cost by reducing the number of parts, facilitating manufacturing, and facilitating assembly.

It is the schematic which shows the side cross section of a Stirling engine. It is the schematic which shows the front cross section of a Stirling engine. It is a perspective view which shows the whole structure of a Stirling engine. It is a perspective view of a crankcase. It is a front view of a crankcase.

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

[Stirling engine]
FIG. 1 is a schematic view showing a side cross section of the Stirling engine 1, FIG. 2 is a schematic view showing a front cross section of the Stirling engine 1, and FIG. 3 is a perspective view of the Stirling engine 1. Note that in FIGS. 1 and 2, the frame 18 described later is not shown.

In each figure, the first direction D1 is the left-right direction D1, the second direction D2 is the vertical direction D2, and the third direction D3 is the front-rear direction D3. In the first direction D1, the arrow direction is the right direction and the opposite direction is the left direction, and in the second direction D2, the arrow direction is the upward direction and the opposite direction is the downward direction. It is a direction, and in the third direction D3, the arrow direction is the front direction, and the opposite direction is the rear direction. The front-rear direction, the left-right direction, and the up-down direction are defined for convenience in order to explain the Stirling engine 1, and differ from the actual directions depending on the direction in which the Stirling engine 1 is installed.

As shown in FIGS. 1 and 2, in the Stirling engine 1, the displacer piston 3 and the power piston 4 are reciprocally housed inside a cylinder 2 in which working gases such as air, helium gas, and hydrogen are sealed. ing. The Stirling engine 1 is a so-called β-type Stirling engine in which the displacer piston 3 and the power piston 4 are housed in the same cylinder 2.

The cylinder 2 has a configuration in which one end is opened while the other end is closed, and the displacer piston 3 is arranged on the closed end side, while the power piston 4 is arranged on the open end side. In the cylinder 2, an expansion space 5 is formed between the closed end portion and the display piston 3, and a compression space 6 is formed between the display 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 an operating space.

The Stirling engine 1 is provided with a heat exchanger 7 that raises and lowers the temperature of the working gas 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 gas by heat input from the outside, a cooler 9 that communicates with the compression space 6 and cools the working gas by heat radiation to the outside, and a heater. The regenerator 10 for connecting the 8 and the cooler 9 is provided. When the displacer piston 3 moves toward the open end side of the cylinder 2, the working gas heated by the heater 8 flows into the expansion space 5, and the temperature of the working gas rises. On the other hand, when the displacer piston 3 moves toward the closed end side of the cylinder 2, the working gas cooled by the cooler 9 flows into the compression space 6, and the temperature of the working gas drops. Therefore, the working gas flows forward and backward between the heat exchanger 7 and the working space in the cylinder 2, so that the internal pressure in the working space of the cylinder 2 changes, and the reciprocating movement of the power piston 4 is promoted.

One end of the heater 8 communicates with the expansion space 5, and the other end communicates with one end of the regenerator 10. The heater 8 heats the working gas passing through the inside by receiving the heat of the exhaust gas generated in the incinerator or the like. Although only two tubular heaters 8 are shown in FIGS. 1 and 2, a large number of heaters 8 are actually provided as shown in FIG.

The other end of the regenerator 10 communicates with the cooler 9. Further, the cooler 9 communicates with the compression space 6. Cooling water flows in the cooler 9 so as to be heat exchangeable with the working gas, and the working gas is cooled by this heat exchange.

The regenerator 10 and the cooler 9 are arranged on the outer peripheral portion of the cylinder 2. The regenerator 10 is composed of, for example, one in which metal fibers and wire mesh are laminated, one in which the flow paths of working gas are arranged in a honeycomb shape, and one in which cotton-like metal fibers are included. Functions as a heat storage type heat exchanger. That is, the regenerator 10 stores heat of the working gas when the high temperature working gas flows from the heater 8 to the cooler 9, while the regenerator 10 stores heat when the low temperature working gas flows from the cooler 9 to the heater 8. The generated heat is dissipated to the working gas.

The Stirling engine 1 is provided with an output extraction device 11 on the open end side of the cylinder 2 that converts the reciprocating motion of the power piston 4 into a rotary motion and outputs rotary power. The output take-out device 11 includes a crankshaft 12 connected to each of the displacer piston 3 and the power piston 4 and pivotally supported in the crankbox 13a in the crankcase 13. Then, one end side of the crankshaft 12 serves as an output shaft, which is connected to the input shaft 16 of the motor generator 15 via the flywheel 14a in the crankcase 13. A flywheel 14b is provided on the other end side of the crankshaft 12.

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

The output take-out device 11 includes a plate 51c fixed to the crankshaft guide groove (through groove) 51a of the displacer piston yoke 51 that reciprocates according to the display piston 3, and a power piston yoke that reciprocates according to the power piston 4. Crankpins 54 to 56 of the crankshaft 12 are fitted to the plates 52c and 53c fixed to the crankshaft guide grooves (through grooves) 52a and 53a of the reciprocating parts) 52 and 53 via bearings 57 to 59, respectively. It is composed of a scotch yoke mechanism.

As shown in FIG. 2, the display support piston yoke 51 is provided with a long crankshaft guide groove 51a in the central portion thereof in a direction (lateral direction) intersecting the axial directions of the crankshaft 12 and the display support piston 3. There is. Reciprocating guide holes (through holes) 51b are bored in the displayer piston yoke 51 on both sides of the crankshaft guide groove 51a in the axial direction (longitudinal direction) of the displayer piston 3. A guide shaft 60 fixed to the crank box 13a is inserted into the reciprocating guide hole 51b of the displacer piston yoke 51 via a linear motion bearing 63 such as a rotor rib bushing. The display support piston yoke 51 is connected to the other end of the rod 66 whose one end is connected to the display support piston 3, and reciprocates in the same direction (vertical direction) as the display support piston 3 in accordance with the reciprocating movement of the display support piston 3.

As shown in FIG. 2, the power piston yoke 52 is provided with a crankshaft guide groove 52a long in the lateral direction in the central portion thereof, and reciprocating guide holes (reciprocating guide holes) are provided on both sides of the crankshaft guide groove 52a. (Through hole) 52b is bored in the vertical direction. A guide shaft 61 fixed to the crank box 13a is inserted into the reciprocating guide hole 52b of the power piston yoke 52 via a linear motion bearing 64. The power piston yoke 52 is connected to the other end of the bridge 67 whose one end is connected to the power piston 4, and reciprocates in the vertical direction in accordance with the reciprocating movement of the power piston 4. Since the power piston yoke 53 has the same shape as the power piston yoke 52, detailed description thereof will be omitted.

As shown in FIGS. 1 and 2, through holes 4a and 67a are provided at the centers of the power piston 4 and the bridge 67 in the axial direction (longitudinal direction) of the power piston 4, and the display piston 3 and the display piston 3 are provided. The connected rod 66 is pierced. The rod 66 is movable relative to the power piston 4 and the bridge 67, and a dynamic sealing mechanism (not shown) such as an oil seal is configured at the insertion portion of the rod 66 in the power piston 4.

As shown in FIG. 1, the crankshaft 12 is connected between a bridge 67 and crank pins 55 and 56 connected via power piston yokes 52 and 53, and a crank pin 54 connected via a rod 66 and a displacer piston yoke 51. Is provided, and the crank pin 54 is attached to the crank pins 55 and 56 having the same phase with a predetermined phase difference (for example, 90 °).

The displacer piston 3 reciprocates with the rotational power of the crankshaft 12, and the working gas moves back and forth between the expansion space 5 and the compression space 6, so that the internal pressure of the working space changes. 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. As a result, 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 crankshafts 12 to rotate by reciprocating the crankshaft guide grooves 52a and 53a in the lateral direction while the crankpins 55 and 56 rotate. 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 the motor generator 15 is transmitted via the flywheel 14a and the input shaft 16. Rotate. Power is generated by the rotation of the motor generator 15.

[Crankcase]
4 and 5 show the crankcase 13. The crankcase 13 has a cross shape (or substantially inverted T shape) in which a first cylindrical portion 131 containing a reciprocating power piston 4 and a second cylindrical portion 132 containing a crankshaft 12 intersect at right angles. ) Is formed.

The first cylindrical portion 131 is arranged outside the cylinder 2. The central axis 131a of the first cylindrical portion 131 extends along the vertical direction D2. The first cylindrical portion 131 has an upper protruding portion 1311 and a lower protruding portion 1312 projecting in opposite directions from the second cylindrical portion 132, respectively. The upper protruding portion 1311 has a larger protruding amount than the lower protruding portion 1312. The upper protrusion 1311 accommodates the power piston 4 and the cylinder 2, and the lower protrusion 1312 accommodates the crank box 13a. The opening of the upper protrusion 1311 is connected to the lower part of the heat exchanger 7. The opening of the lower protrusion 1312 is closed by a disk-shaped lid member 1313. The crank box 13a is fixed to the lid member 1313.

The second cylindrical portion 132 is arranged outside the crankshaft 12. The central axis 132a of the second cylindrical portion 132 extends along the left-right direction D1. The second cylindrical portion 132 has a left protruding portion 1321 and a right protruding portion 1322 projecting in opposite directions from the first cylindrical portion 131, respectively. The left protruding portion 1321 has a larger protruding amount than the right protruding portion 1322. The left protruding portion 1321 accommodates the crankshaft 12 and the input shaft 16, and the right protruding portion 1322 accommodates the crankshaft 12. The opening of the left protrusion 1321 is connected to the motor generator 15. The opening of the right protrusion 1322 is closed by a disk-shaped lid member 1323.

The crankcase 13 includes a frame 18 for installing the crankcase 13 in an operating place. The frame 18 is integrally formed with the crankcase 13. Here, as a method of integrally forming the frame 18 with the crankcase 13, for example, a method of joining the separately formed crankcase 13 and the frame 18 by welding or the like, and integrally forming the crankcase 13 and the frame 18. Examples thereof include a method of integrally molding by casting and the like, a method of joining the separately formed crankcase 13 and the frame 18 with bolts and the like to integrate them. In this embodiment, an example in which the separately formed crankcase 13 and the frame 18 are joined by welding is shown.

By integrally forming the frame 18 with the crankcase 13, the cost can be reduced by reducing the number of parts, facilitating manufacturing, and facilitating assembly. Further, by forming the frame 18 integrally with the crankcase 13, it is possible to reduce the size and weight by simplifying the shape.

Further, by forming the frame 18 integrally with the crankcase 13, not only the crankcase 13 but also the frame 18 becomes a strength member, so that damage to the crankcase 13 due to the high-pressure working gas inside the crankcase 13 is suppressed. can do. Further, the frame 18 can suppress expansion and deformation of the crankcase 13 due to the working gas inside the crankcase 13, and can suppress vibration of the Stirling engine 1.

The frame 18 has a square tubular shape as a whole. That is, the frame 18 has four plate members (top plate 181, bottom plate 182, left side plate 183, and right side plate 184) that form a square cylinder. The upper surface plate 181 and the lower surface plate 182 are arranged so as to be orthogonal to the central axis 131a of the first cylindrical portion 131. Further, the left side plate 183 and the right side plate 184 are arranged so as to be orthogonal to the central axis 132a of the second cylindrical portion 132.

The top plate 181 and the bottom plate 182, the left side plate 183, and the right side plate 184 have two protrusions 1311, 1312 of the first cylindrical portion 131 and two protrusions 1321, 1322 of the second cylindrical portion 132. Is combined with. As a result, since the square tubular frame 18 having strength and rigidity is coupled to the crankcase 13 so as to surround the periphery, it is possible to suppress large vibration in a specific direction or portion of the Stirling engine 1. it can.

The frame 18 is formed between the protruding portions 1311, 1312 protruding from the second cylindrical portion 132 of the first cylindrical portion 131 from the tip portion to the intermediate portion in the protruding direction, and the first of the second cylindrical portions 132. The protrusions 1321, 1322 protruding from the cylindrical portion 131 are coupled to the crankcase 13 between the tip portion in the protrusion direction and the intermediate portion.

In this embodiment, the top plate 181 is coupled to the opening of the upper protrusion 1311 of the first cylindrical portion 131. Further, the lower surface plate 182 is coupled to the opening of the lower protrusion 1312 of the first cylindrical portion 131. The left side plate 183 is connected to an intermediate portion between the opening of the left protrusion 1321 of the second cylindrical portion 132 and the connection portion with the first cylindrical portion 131, that is, the middle portion of the left protrusion 1321. .. Further, the right side plate 184 is coupled to the opening of the right protruding portion 1322 of the second cylindrical portion 132. As a result, the frame 18 acts as a structure or rib that reinforces the weak portion (opening of the protrusion and the middle abdomen) of the crankcase 13, so that the pressure resistance of the crankcase 13 is improved and safety against breakage is improved. Contribute to improvement.

As shown in FIG. 3, when the Stirling engine 1 is installed in the operating place with the bottom plate 182 of the frame 18 facing downward in the vertical direction, the heater 8 is in a state of facing upward in the vertical direction. The bottom surface (corresponding to the third end surface) of the bottom plate 182 is substantially flat, and can be easily installed with the bottom surface of the bottom plate 182 of the frame 18 facing downward in the vertical direction. The bottom plate 182 may be directly fixed to the operating place, but may be fixed via the spacer 182a as shown in FIG.

The frame 18 has a front end surface 185 formed symmetrically with respect to a virtual central surface 133 (see FIG. 4A) including a central axis 131a of the first cylindrical portion 131 and a central axis 132a of the second cylindrical portion 132. It has (corresponding to the first end face) and rear end face 186 (corresponding to the second end face).

The front end surface 185 and the rear end surface 186 are flat surfaces, and the Stirling engine 1 can be easily installed in the operating place with the front end surface 185 or the rear end surface 186 of the frame 18 facing downward in the vertical direction. When the Stirling engine 1 is installed in the operating place with the front end surface 185 or the rear end surface 186 of the frame 18 facing downward in the vertical direction, the heater 8 is in a state of facing the horizontal direction.

By directing the front end surface 185 of the frame 18 downward in the vertical direction, the motor generator 15 can be installed toward the right side of the Stirling engine 1 when viewed from the lower surface plate 182 side of the frame 18. On the other hand, by directing the rear end surface 186 of the frame 18 downward in the vertical direction, the motor generator 15 can be installed toward the left side of the Stirling engine 1 when viewed from the lower surface plate 182 side of the frame 18. Since the front end surface 185 and the rear end surface 186 of the frame 18 are formed mirror-symmetrically, the installation direction can be easily changed in this way.

Although the embodiments of the present invention have been described above with reference to the drawings, it should be considered that the specific configuration is not limited to these embodiments. The scope of the present invention is shown not only by the description of the above-described embodiment but also by the scope of claims, and further includes all modifications within the meaning and scope equivalent to the scope of claims.

1 Sterling engine 2 Cylinder 3 Displacer piston 4 Power piston 12 Crankshaft 13a Crankbox 13 Crankcase 131 First cylindrical part 131a Central axis of the first cylindrical part 132 Second cylindrical part 132a Central axis of the second cylindrical part 15 motor generator 18 frames

Claims (5)

A crankcase formed in a cross shape by intersecting a first cylindrical portion containing a reciprocating piston and a second cylindrical portion containing a crankshaft rotatable by the reciprocating movement of the piston.
A frame for installing the crankcase in an operating place is provided.
The frame is a β-type Stirling engine integrally formed with the crankcase. The frame has a first end face and a second end face formed symmetrically with respect to a central axis of the first cylindrical portion and a virtual central plane including the central axis of the second cylindrical portion. The β-type Stirling engine according to 1. The β-type Stirling engine according to claim 2, wherein the frame has a flat third end surface orthogonal to the central axis of the first cylindrical portion. The frame is formed between the tip of the first cylindrical portion in the protruding direction of the protruding portion protruding from the second cylindrical portion to the intermediate portion, and the first cylindrical portion of the second cylindrical portion. The β-type Stirling engine according to any one of claims 1 to 3, which is coupled to the crankcase between the tip portion in the protruding direction and the intermediate portion of the protruding portion protruding from the engine. The frame has a square tubular shape and has a square tubular shape.
The four plate members constituting the square cylinder are formed from two projecting portions of the first cylindrical portion protruding from the second cylindrical portion and from the first cylindrical portion of the second cylindrical portion. The β-type Stirling engine according to any one of claims 1 to 4, which is coupled to each of two protruding portions.

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