JPH0249960A - Stirling engine - Google Patents

Abstract

PURPOSE:To reduce a loss caused by an inflow of fluid into bounce space by respectively providing a flow path communicating with a clearance of a displacer rod from gas spring space and a flow path, provided with a check valve, communicating with the bounce space from the clearance of the displacer rod. CONSTITUTION:When a displacer 30 is, for instance, lowered, because the volume of compression space 46 decreases while the volume of expansion spacer 54 increases, helium in the inside of the compression space 46 and a cooler 28 moves passing through a regenerator 29 and a heater 27 to the expansion space 54. Here following lifting of the displacer 30, two or more flow paths 38, 40 communicate through a clearance 39, thus when a pressure in gas spring space 37 is lower than a pressure in bounce space 41, the pressure is equalized by allowing the helium to flow into the former 37 from the latter 41. When the displacer 30 is lowered, a reverse flow of the helium in the gas spring space 37 to the bounce space 41 is prevented by a check value 50, thus an increase is eliminated of a friction loss or the like.

Description

[Detailed description of the invention] Industrial applications This invention relates to Stirling engines.

Conventional technology Conventionally, this type of Stirling engine has, for example,
There is a structure as shown in Figure 2 (Japanese Unexamined Patent Publication No. 58-4
(No. 7141) This is an example of a displacer type and free piston type Stirling engine.

Reference numeral 1 denotes a container in which working fluid of the Stirling engine (hereinafter abbreviated as helium) such as helium or nitrogen is sealed. 2 is a heater for heating the working fluid, 3 is a cooler for cooling the working fluid, and 4 is a regenerator. δ is a displacer that moves up and down while sliding on the inner wall of container 1, 6 is a piston that moves up and down while sliding on the inner wall of container 1, 7 is a rod coupled to piston 6, and 8 is coupled to the rod. This armature constitutes a linear generator together with the stator 9.

Further, 10 is a rod that is a part of the displacer 5, II
12 is a gas spring space surrounded by the rod 10 and the container 1; 13 is a gas spring space provided within the rod 10 and communicates with the gap 15 between the rod 10 and the bearing 11 from the gas spring space fm12; The flow path 14 is a flow path whose one end closes into the gap 15 from inside the container l and whose other end closes into the bounce space 16. matches when .

Reference numeral 17 denotes a flow path provided in the piston 6 and communicating from the compression space 18 to the gap 20 between the piston 6 and the container 1.

21 is a flow path whose one end closes into the gap from inside the container I and whose other end opens into the bounce air rW116. Match.

Further, the compression chamber m1B and the compression space 19 communicate with each other through a communication hole 22 with small flow resistance provided in the container 1,
The bounce space 16 and the bounce space 24 communicate with each other through a plurality of communication holes 23 provided in the armature 8 and having low flow resistance.

The action will be explained below. When the displacer 5 is lowered, the volume of the compression space 19 decreases and the volume of the expansion space 25 increases, so that the pressure in the compression space 19 increases with the expansion air fm25.
Due to this pressure difference, the low-temperature helium in the compression space 19 and cooler 3 flows through the regenerator 4 and heater 2 toward the expansion space 25. The regenerator 4 is heated by the regenerator 4 and the heater 2, and the regenerator 4 is cooled in turn. Since the low-temperature helium is heated in this way, the pressure in the combined space of the compression space 18, 19, cooler 3, regenerator 4, heater 2, and expansion space 25 (hereinafter referred to as the working space) increases. Pull down the piston 6. At this time, the piston 6 applies work to the linear motor 8.9 via the rod 7.

On the other hand, as the displacer 5 continues to fall, the pressure in the gas spring space 12 gradually increases, and finally the displacer 5 stops falling and begins to rise again. When the displacer 5 rises, the volume of the compression space 19 increases and the volume of the expansion space 25 decreases.
The pressure becomes higher than the pressure in the compression space 19, and due to this pressure difference, the high temperature helium in the expansion space 25 and the heater 2 flows through the regenerator 4 and the cooler 3 toward the compression space 19. At this time, the helium is cooled by the regenerator 4 and the cooler 3. The regenerator 4 is then heated in reverse. Since the high-temperature working fluid is cooled in this way, the pressure in the working space is lowered and the piston 6 is pulled up. At this time, the piston 6 applies work to the linear motors 8 and 9 via the rod 7.

On the other hand, as the displacer 5 continues to rise, the pressure in the gas spring space 12 gradually decreases, and finally the displacer 5 stops rising and begins to descend.

In the process described above, helium converts a part of the heat obtained by the heater 2 into work for the linear motors 8 and 9 via the rod 7, and discards the part to the cooler 3. Usually, the phase angle of the position of the displacer 5 leads the phase angle of the position of the piston 6 by 60° to 90°.

In addition, in order to keep the center position of the movement of the displacer 5 and the piston 6 constant during operation, it is necessary to average the lP1 phase leaps of each part in the container 1 (hereinafter, the average refers to the average of one cycle unless otherwise specified). It is necessary to keep the pressures equal.

When the piston 6 reaches the center of its movement, the flow path 17 and the flow path 21 communicate with each other, so that the pressure in the compression space 18 becomes equal to the pressure in the bounce space 16, so that the average position of the piston 6 is kept constant. It will be done.

However, if there is no flow path 13 or 14, the helium in the gas spring space 12 will pass through the gap 15 and enter the compression space 1 if averaged over one cycle.
As the gas spring space 12 is closed during operation, the pressure in the gas spring space 12 becomes lower than the pressure in the expansion space 25 and the pressure in the compression space 19, so that the average position of the displacer 5 gradually decreases and collides with the container. .

The flow paths 13 and 14 are provided to prevent such a drop in the average position of the displacer 5 and keep it constant. That is, when the displacer 5 comes to the center of its movement, the flow passages 13 and 14 communicate with each other, so that when the pressure in the gas spring space 12 is lower than the pressure in the bounce space 16, the bounce space 1
The helium of No. 6 passes through the flow channels 14 and 13 and enters the gas spring space 1.
2 and equalize the pressure. Note that the volume of the bounce space 16 is larger than the volumes of the gas spring space 12 and the working space, and its pressure amplitude is smaller than the other two.

In this way, on average there are 16 bounce spaces and 1 gas spring space.
2. By circulating the compression space 19 and the bounce space RTL 16 in this order and keeping the average pressure in these three spaces equal, the average positions of the displacer 5 and the piston 6 are kept constant.

This is the only problem that the invention attempts to solve.In a structure like this, it is possible to replenish helium that would otherwise leak from the gas spring space 12 to the compression space 19 in only one direction from the bounce space 16 to the gas spring space 12. Even though the average position of the displacer 5 is constant, a backflow occurs from the gas spring space 12 to the bounce space 16 through the gas spring space 12 and the gap 15, so the flow path is smaller than when there is no backflow. The absolute value of the flow rate passing through 14 increases, and the loss due to friction and the like increases. As a result, the engine's indicated efficiency is reduced.

Therefore, the present invention prevents the flow from the gas spring space to the bounce space or the working space through a flow path that communicates the gas spring space with the bounce space or the working space, thereby reducing friction loss, etc., thereby increasing the indicated efficiency of the engine. The purpose is to increase the

Means for solving the problem and technical means for solving the above problem are a flow path B that runs from the gas spring space through the displacer rod to the gap S between the bearing and the displacer rod, and one end of the flow path B is connected to the bearing from the side. It is characterized in that it has a flow path C that communicates with the gap S and the other end communicates with the working space or the bounce space, and a check valve is provided in the flow path C.

action The effect of this technical means is as follows.

That is, the check valve provided in the flow path C prevents the helium in the gas spring space from flowing back into the bounce space or the working space, and allows the same amount of helium that leaks from the gas spring space into the low-temperature space into the bounce space or the working space. It acts to supply gas from the operating space to the gas spring space.

EXAMPLE An example of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 26 denotes a container in which a working fluid for the Stirling engine (hereinafter abbreviated as helium) such as helium or nitrogen is sealed. 27 is a heater for heating the working fluid, 28 is a cooler for cooling the working fluid, and 29 is a regenerator. 3° is a displacer that moves up and down while sliding on the inner wall of the container 26; 31 is a piston that moves up and down while sliding on the inner wall of the container 26; 32 is a rod connected to the piston 31; 33 is a rod 32; The combined armature and stator 34 constitute a linear generator.

Further, 35 is a rod that is a part of the displacer 3o;
6 is a bearing which is a part of the container 26, 37 is a gas spring space surrounded by the rod 35 and the container 26, and 38 is provided in the rod 35 and communicates from the gas spring space 37 to the gap 39 between the rod 35 and the bearing 36. The communicating flow path 40 is a flow path with one end opening into the gap 39 from inside the container 26 and the other end opening into the bounce space 41. Matches when in position. 42 is a compression space 43 provided within the piston 31
A flow path 44 communicates with a gap 45 between the piston 31 and the container 26 , one end of which opens into the gap 45 from inside the container 26 and the other end opens into the bounce space 41 , and the flow path 42
and the flow path 44 coincide when the piston 31 is at the center of its movement.

The compression space 43 and the compression space 46 communicate with each other through a communication hole 47 with small flow resistance provided in the container 26, and the bounce space 41 and the bounce space 4 are connected to the armature 33.
They communicate through a plurality of communication holes 49 with low flow resistance provided in the.

Further, 50 is a check valve, 51 is a flow control valve, 52 is a displacer position detector, and 53 is a control device.

The action will be explained below. When the displacer 30 is lowered, the volume of the compressed air r:ff46 decreases and the volume of the expansion space 54 increases, so the pressure in the compression space 46 becomes higher than the pressure in the expansion space 54, and this pressure difference causes the compression space 46 to The low temperature helium in the cooler 28 flows through the regenerator 29 and the heater 27 towards the expansion space 54, where the helium is heated by the regenerator 29 and the heater 27, and the helium is heated by the regenerator 29 and the heater 27. On the contrary, the container 29 is cooled.

Since the low-temperature helium is heated in this way, the compressed air r
:Y43.46. cooling! 28, g raw 829, heater 2
7. The pressure in the space including the expansion space 54 (hereinafter referred to as the working space) increases and the piston 31 is pulled down. At this time, the piston 31 is connected to the linear motor 3 via the rod 32.
Work on 3 and 34. On the other hand, displacer 30
As the pressure continues to decrease, the pressure in the gas spring space 37 gradually increases, and finally the displacer 30 stops decreasing and begins to increase. When the displacer 30 rises, the volume of the compression space 46 increases and the volume of the expansion space 54 decreases, so that the pressure in the expansion space 54 becomes higher than the pressure in the compression space 46, and this pressure difference causes the expansion space 54 to increase in volume.
The high temperature helium in the heater 27 is transferred to the regenerator 2.
9. The helium flows through the cooler 28 towards the compression space 46, where it is cooled by the regenerator 29 and the cooler 28. The regenerator 29 is then heated in reverse.

Since the high-temperature working fluid is cooled in this way, the pressure in the working space is lowered and the piston 31 is pulled up. At this time, the piston 31 is connected to the linear motor 33 via the rod 32.
Work against 34.

On the other hand, as the displacer 30 continues to rise, the pressure in the gas spring space 37 gradually decreases, and finally the displacer 3
0 has stopped rising and now begins to fall in the opposite direction. In the process described above, helium converts a part of the heat obtained by the heater 27 into work for the linear motors 33 and 34 via the rod 32, and a part is discarded to the cooler 28. . Usually, the phase angle of the position of the displacer 30 is 60'' to 90° with respect to the phase angle of the position of the piston 31.
It's progressing.

Furthermore, as described in the conventional example, if there are no flow paths 38 and 40, helium in the gas spring space 37 will leak into the compression space 46 through the gap 39 as the operating time passes, and as a result, the average position of the displacer 30 will be It descends over time and finally collides with the container 26.

Flow paths 38 and 40 are provided to prevent this and maintain the average position of the displacer 30 at the target value. That is, during the vertical movement of the displacer 30, the flow path 38 and the flow path 40
When the displacer 30 is in communication with the displacer 30 through the gap 39 (this position of the displacer 30 is abbreviated as the centering position), if the pressure in the gas spring space 37 is lower than the pressure in the bounce space 41, helium flows from the bounce space 41 into the gas spring space 37. Equalize the pressure.

However, when the displacer 30 is lowered from the centering position, the helium in the gas spring space 37 flows into the flow path 38 and the gap 3.
9 or flow path 38 into the bounce space 41, friction loss etc. will increase and the indicated efficiency of the engine will be reduced. Therefore, the check valve 50 prevents the backflow. Therefore, the loss due to backflow is reduced and the indicated efficiency of the engine is increased. Furthermore, the position detector 52 detects the position of the displacer 30 and sends a position signal to the control device 53.
The control device 53 calculates the average position of the displacer 30 from this signal and compares it with the target value, and if it is higher than the target value, the flow f is
The opening degree of the t control valve 51 is decreased, and when it is lower than the target value, the opening degree of the flow rate control valve 51 is increased. Further, the control device 53 controls the opening degree of the flow rate control valve 51 to be as small as possible unless the average position of the displacer 30 changes, so that the flow rate passing through the flow path 40 is kept to the minimum necessary. Therefore, the loss caused by helium passing through the flow path 40 is kept to a minimum. Uchi flow control valve 5
12 position detector 52. The flow depends on the operation of the control device 53.
There is also the effect that the loss due to the passage of helium through 1s40 is reduced, the illustration efficiency is increased, and the average position of the displacer can be controlled.

As described above, this embodiment has a check valve of 50 degrees and a flow control valve of 51 degrees in addition to the conventional example. Position detector 52. Since the control device 53 is provided, the provision of the check valve 50 has the effect of reducing loss due to backflow and increasing the indicated efficiency of the engine. Control valve 515 position detector 52. Since the control device 53 is provided, by controlling the opening degree of the flow rate control valve 51, the loss caused by helium passing through the flow path 40 is reduced, the indicated efficiency is increased, and the average position of the displacer is reduced. There is also the effect that it becomes possible to control.

In this embodiment, the flow path 40 communicates the gap 39 with the bounce space, but the present invention is not limited to this, and may communicate the gap 39 with the working space. Further, in this embodiment, a linear motor is used as the engine load, but the present invention is not limited to this, and a pump or a compressor may also be used.

Effects of the Invention The present invention has a flow path B which passes from the gas spring space through the inside of the displacer rod and communicates with the gap between the bearing and the displacer rod, and one end of which has a narrow end that connects from the side of the bearing to the gap rW1s between the bearing and the displacer rod. is a Stirling engine that has a flow path C leading to the working chamber or bounce space, and a check valve provided in the flow path C, so that gas flows from the gas spring space through the flow path C to the working chamber or bounce space. Since the amount of working fluid can be reduced, the loss caused by this drift can be reduced.

This has the effect of increasing the indicated efficiency of the engine.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of a Stirling engine according to an embodiment of the present invention. FIG. 2 is a vertical cross-sectional view of a conventional Stirling engine. 26... Container, 27... Heater, 28
...Cooler, 29...Regenerator, 30.
... Displacer, 31 ... Piston, 32 ... --- Port, 33 ... Armature, 34 ... Stator, 35 ... ····rod,
36...Bearing, 37...Gas spring space, 38, 40...Flow path, 50...Check valve, 51... Flow control valve, 52...
Position detector, 53... Control device, 46.43.
...Compression sky, 41.48...Bounce sky rrI. Name of agent Patent attorney Toshio Nakao (1 person) Figure 1 Procedural amendment (method) September 8, 1989 ■Indication of case 1988 Patent Application No. 54218 2 Name of invention Stirling engine - Make amendments Relationship with the case filed by Patent Application Address 1006 Oaza Kadoma, Kadoma City, Osaka Name (582) Representative of Matsushita Electric Industrial Co., Ltd.
Akio Tanii

Claims (3)

[Claims] (1) A container, a working fluid sealed in the container, and a work fluid arranged so as to divide the space inside the container into a working space and a bounce space, and working in the working space while moving with respect to the container. a piston for receiving work from a fluid and movable relative to the wall of the vessel to divide the working space into a hot space in which a hot working fluid is present and a cold space in which a cold working fluid is present; a flow path A that communicates the displacer disposed with the high temperature space and the low temperature space;
A heater that heats the working fluid in the high temperature space or on the high temperature space side of the flow path A, a cooler that cools the working fluid in the low temperature space or the low temperature space side of the flow path A, and a part of the container. a displacer rod forming a part of the displacer; a gap S between the bearing and the displacer rod; a gas spring space surrounded by the container and the displacer and communicating with the low temperature space via the gap S; A flow path B leading from the space to the gap S through the displacer rod, a flow path C having one end leading to the gap S from the bearing side and the other end leading to the operating space or the bounce space, and a flow path C provided in the opposite direction. Stirling engine with stop valve. (2) The Stirling engine according to claim 1, further comprising a valve provided in the flow path C that can change the flow resistance. (3) Claim 2, further comprising a control device for controlling the opening degree of a valve whose flow resistance can be changed by a signal indicating the position of the displacer.
The Stirling engine described in.