JPS5896147A - Stirling cycle engine - Google Patents

Abstract

PURPOSE:To prevent reduction of thermal efficiency in a gas engine consisting of two long pistons and one short piston respectively provided with a guide piston, by forming an oil removable space and a variable gas space in each said piston. CONSTITUTION:Power is taken out through guide pistons 60, 61, 62 from the heat cycle of the variable space 45, 46, 49, 50 for an operating fluid formed by long pistons 43, 44 and a short piston 47. An operating fluid at a high pressure is fed into the spaces 63, 64 formed in the lower portion of said long pistons 43, 44 and into the space 72 in the lower portion of said short piston 47, while said spaces 63, 64, 72 are communicated with each other, thus, the inflow of an oil from the guide piston side is prevented. Moreover, a space 69 is formed in each said pistons 43, 44, 47. In said space 69, an oil is splashed at a low pressure and returned to a crank case. Further, a piston 110 with a small diameter is disposed in the upper portion of said short piston 47. In the case that the pressure of the operating fluid is lowered, the operating fluid in the crank case is led from 116 into said piston 47 through a filter 113 and a purifier 114 and compressed by said piston 110 and then returned to the operating space, thus maintaining the performance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses a working fluid mainly as a gas (in special cases, there are also liquids, mixed gases, and dual gases), and a thermal cycle or ideally two isovolumic processes and two isothermal processes. It concerns the equipment configuration of a Stirling cycle engine consisting of processes.

The Stirling engine uses the cold heat of liquefied natural gas to generate force, or heats it with fossil solvents, solar heat, etc., generates force, and then applies power from a motor to the engine to generate extremely low temperatures. It is a reversible cycle engine that can be used as a refrigerator or a heat pump.

These purposes and uses are well known;
Since this is briefly described in detail in the applicant's patent, the drawbacks of the general σJ double-acting type prime mover, the equipment configuration of the present invention, its features, and its principle operation will be described here.

The typical equipment configuration for the original Stirling gas engine (hereinafter referred to as gas engine) is as follows:
As shown in the figure, it is a double-acting e type that compresses and expands the working fluid at both ends of the piston, and consists of four piston cylinders.

1 to 4 are cylinders, 5 to 8 are pistons, and 9 to 12 are piston ronds (not shown) for reciprocating mechanism (crankshaft, oscillating plate 1 rotation oblique &, 2 series or 8 series crankshaft, etc.) They are connected to each other so that they can reciprocate with a phase difference of 90 degrees.

Working fluid (usually gas, 7 leon, hydrogen.

Helium, etc. or mixed gases (as a special case, methane water),
Heater chips 21-24.
Heat storage devices 25-28. It is sealed in an interior connected via heat radiators 29 to 82 at a pressure of several 10 atm to 200 atm.

However, 88 to 86 are piston rings, and 87 to 40 are gland backings that seal the working fluid with ronds, which prevents high pressure (100 to 200 pressure) working fluid from leaking into the crankcase of the piston reciprocating mechanism. prevent When the heater chips 21 to 24 are heated to 600 to soo'c, the working fluid works to push the pistons 5 to 8 in the expansion spaces 13 to 16, respectively, and at the same time, in the compression spaces 17 to 20, the power is activated. In order to push the fluid,
The difference between expansion work and compression work is obtained as effective work from a piston reciprocating mechanism (not shown). However, heatsink 29~
82 radiates the heat to the atmosphere since the working fluid has a temperature of 50 to 120° C. when compressed. Ideally, this prime mover has four cycles of working fluid, as shown in Figure 2.
With a phase difference of 0 degrees, each fluctuates sinusoidally at high pressure (140
~250 atm (example in Figure 2, the horizontal axis is the crank angle), and power is generated, but each expansion space and the compression space of each cycle with a 90 degree phase difference are connected to the same piston σ). The piston ring is formed on the ground through the piston ring. For example, the expansion space 14 in FIG. Heater tube 22. Heat storage device 26, heat radiator 80. Compression section 1
Assuming that the pressure change of the working fluid during the 9th cycle is Tr12 (b) in the diagram, the highest pressure is 250 atm at a crank angle of about 150 degrees, and if the piston ring 84 is not completely sealed at this time, the expansion space 14 will be damaged. High temperature (500-70
0℃) working fluid (e.g. hydrogen, helium, water, etc.)
The problem is that it leaks to the FI-contracted space]8 of cycle a (180 atm at point χ at this time) where the crank angle is advanced by 90 degrees.

As a result, the mass of the working fluid increases in one cycle, b
In the cycle, the heat balance of the heater chamber, heat storage device, and radiator σ created from the optimal design values (temperature, flow rate, pressure, etc.) will be disrupted, leading to a decrease in output and thermal efficiency.

2) Since the minimum and maximum pressures of the working fluid in each cycle are different, the work force generated is also different, resulting in imbalance and vibration.T8) Due to this vibration, each piston and piston rod also vibrate. As a result, the sealing performance of the working fluid due to these is greatly reduced.
The amount of leakage from the rod seal and piston ring also increases, causing the engine to stop.

4) Especially when used in a prime mover, if high-temperature working fluid leaks from the piston ring, the piston ring, which is mainly made of plastic, will be heated, which will accelerate deterioration and reduce the durability of the prime mover.

The present invention eliminates the above-mentioned drawbacks of conventional gas engines.
This is related to the configuration of the equipment.

Figure 8 shows the configuration of the machine and equipment of the present invention. A relatively long piston 48.44 with a T0 guide piston and its relatively long cylinder 41.42 (hereinafter referred to as long cylinder) allow the working fluid to be Volume variable space 45.46 (
The working fluid variable space (hereinafter referred to as "cute space") is formed by a relatively short piston 47 with a guide piston and a relatively short cylinder 48 (hereinafter referred to as "short piston" or "short cylinder"). A heat exchanger 51.
53a, a heat storage device 58154, and heat exchangers 55 and 56. The long piston 48, 44 and the short piston 47 extract power (not shown) via a piston rod 57, 58, 59 and a guide screw 60, 61, 62, or are directly connected to an electric motor or generator, or are connected to a gear, chain, etc. The piston reciprocating mechanism (rotating swash plate, rocking plate)
The gas spaces 68 and 64 formed by the vertical movement of the 0-length piston 48.44 connected to a plate (for example, a single-axis or multi-axis crankshaft, etc.) and the gland seal 68 are the main parts of the present invention.65. 66 fluid ports are connected by pipes, approximately 180 mm of the long piston 48.
Even if it moves up and down with a phase difference of degrees, the working fluid will not be compressed here. Or this gas space part and space part 72&:
When the working fluid is at a suitable pressure @ valve compression g as shown in Figure 5
It is supplied by A and others. Returning to FIG. 8, the gland seal 68. Shape jL with oil remover 71! The purpose of this space 69 is to remove oil that has entered from the guide piston 60°61.
00 atm) and a gas space 6 for the working fluid sealed therein.
8° 64 and the space 72 to prevent oil from entering. Therefore, the oil removed in the space 69 is removed from the connection lower 0, although it is not shown in the figure.
A return T mechanism is provided in the rL piston reciprocating mechanism and oil sump. In addition, No. 78 Clean working fluid Q) Supply port? Reference numeral 4 indicates a piston ring, and reference numeral 75 indicates a guide cylinder, which are not shown in the drawings, but are integrally packaged with the crankcase in the embodiment.

The major difference between Stirling-Seki and Ding, or Gas-Seki, from white light engines is that the working fluid is sealed at high pressure, a so-called closed cycle, and the working fluid must be completely free of oil, etc. It is a must. In the former case, if the working fluid leaks and the pressure drops, the output will drop accordingly, and in the latter case, if even a small amount of oil gets into the motor, the oil will carbonize and heat up. This is because the generated power decreases due to a decrease in the thermal efficiency of the exchanger and heat storage device, and in the case of a gas refrigerator, the oil solidifies and the refrigerator becomes unable to rotate.

Therefore, in the present invention, the high pressure working fluid variable space 45. formed by the short and long pistons and their respective cylinders.
49.50.46 and guide pistons 60.61.62 which are normally lubricated with oil and their piston reciprocating movements 1li
A gas space 68, 64 and a space 72 are provided between the crankcase and the crankcase, which contains clean working fluid at medium pressure, to create a pressure difference. By providing a space 69 that can be returned to the case, oil will not enter the variable volume space, which operates at high pressure, and the numerous heat exchangers and heat accumulators. As shown in Fig. 5, the shape of the relatively long piston/cylinder is made into a convex type or with multiple stages of small piston parts, so that two pistons (LV, 2V) or more can be used. Several working fluid expansion or compression variable spaces can be configured.

Also, in the short piston 47 shown in Figure 8, as shown in Figure 5, a small diameter piston 110t is connected to the upper part, and the suction valve I11. Discharge valve 112. Oil filter 118. Purifier 114. It can be configured as a compressor for working fluid by attaching a valve 115, so that even if the pressure of the working fluid decreases, it can be returned to a cleaner state than the working fluid Tt116 in the crankcase. Working fluid always leaks little by little from the variable space made up of the long and short pistons into the crank chamber through the pistons, rings, ronds, and seals.

Therefore, by connecting a small piston to a short piston and attaching suction and discharge valves to configure a compressor, it is possible to clean (return) working fluid from the crank chamber, and the gas space 68, 64 can be Space 49.50, space 72σ
) The pressure can be appropriately adjusted through the buff tank 117 and the regulating valve 118. That is, in the same way as increasing the pressure in the variable space to prevent it from entering from the crankcase, in the case of a prime mover, the generated power is adjusted to the refrigeration temperature and refrigeration output in a refrigeration system. Incidentally, instead of improving the short piston and adding the compressor function (independent compression l!i), the same effect can be achieved.

This long piston is shown in Figure @6! Like the piston cap 80 and suction check valve 81 made of thin-walled ceramic, etc. Is it the piston element 88 that includes the safety valve 82 or the port 84σJ? The inside 87 of the piston cap 80 has a variable space 45 which can be at a high temperature or an extremely low temperature.
In order to prevent heat loss due to the temperature difference between the upper part 89 of the cap and room temperature due to the heat radiation, a metal plate 85 with many small holes is placed on top of the metal plate 85 to eliminate convection heat loss due to the internal fluid. The heat insulating materials 86 are alternately laminated. By pre-filling the same fluid as the working fluid inside the cap with the suction check valve 81 at high pressure, even if the variable space 45, 46 becomes high pressure, the piston cap 8
0 can be made into a thin-walled cylindrical shape to reduce weight, so losses related to the piston reciprocating mechanism can be reduced. A typical piston has a diameter of 1001N and is subjected to external pressure, so even heat-resistant alloys will deform unless they are thicker than 1Oa. In addition, since there is a suction check valve 81 with a set suction pressure, the gas empty area ea
, 64 pressure is abnormal (even when it becomes high).
It can be collected inside the piston cap 86. Also, since there is a safety valve 82, this pressure stage? The piston cap 80 does not break even when the pressure is set at the maximum pressure of the working fluid in the variable space or at an intermediate pressure, and the piston cap 80 can be made thinner and lighter than the piston of a gas engine. For example, it may have a diameter of 1001111 mm and a wall thickness of 8 fl. Fig. 4 is a diagram of the perspiration power fluctuation of the working fluid in the gas engine of the present invention (the horizontal axis is the crankshaft angle).
0 (If the piston cap is sealed so that the amount of perspiration is 1, the pressure fluctuation applied to the piston cap will be about ±50 atm.In other words, if it is sealed at room temperature and at about 100 atm, when the steady state is reached, there will be a temperature gradient inside the piston cap.) is formed, expands and increases pressure to about 2
00 atmospheres. In addition, 88 is the piston ring 57 (59
), the piston rod 90 is a gas seal, a heat insulating material 86 and a heat radiation shield plate are alternately laminated on the piston cap 80, and an intake check valve 81. By attaching the piston element 88 with 82 safety valves attached using bolts 84, a long piston for a gas engine (the piston cap becomes hot or extremely cold) can be manufactured independently.

When actually installed in a gas engine, the guide piston is 60.62' from the crankcase and piston reciprocation mechanism.
! A-Threaded piston rod 57゜59σ] Threaded part 98
Tighten with a nut 91 and washer 92 inside the piston element. 94 is a small hole for rotating or fixing the long piston. In addition, when the working fluid is helium gas, in the prime mover, the fluid in the piston cap is argon, or other gas Trg & human check valve 81σ).Although not shown, the safety valve 82 is not attached and the shutoff valve is used to seal the fluid. You may do so. Further, even in the case of using a refrigerator, a gas that solidifies and becomes a vacuum when the temperature reaches a low temperature may be filled in advance.

Fig. 7 shows an example of the arrangement of long and short piston groups applied to four sets of gas engines according to the present invention. This is a case where the long bistus ν with a piston is also arranged at a bank angle of 45 degrees. In this case, 12 pistons reciprocate, but the 8 long pistons generate power at each crank angle of 45 degrees, and at the same time, the 4 short pistons also generate ridges of working fluid (negative power), so the dynamic balance is balanced. is often used, and there is almost no occurrence of photographing. In addition, since short pistons are arranged at both ends of the crankshaft, it is easy to assemble heat exchangers (four sets of 55 and 56 in Fig. 8 are required, also called heater tubes) that are heated to high temperatures.

[Brief explanation of drawings]

Figure 1 is a diagram of the principle of a double-acting gas engine.
Fig. 2 is an explanatory diagram of pressure fluctuations in the double acting system, Fig. 8 is a diagram showing the basic equipment configuration, Fig. 4 is an explanatory diagram of pressure fluctuations according to the present invention, Fig. 5 is a diagram of the piston principle, and Fig. 6 is a diagram illustrating pressure fluctuations according to the present invention. The figure is a piston structure diagram, and FIG. 7 is an explanatory diagram of the arrangement of long and short piston groups when four sets of gas engines are applied to a large-scale prime mover. 41.42.48...Cylinder, 48@44...Relatively long piston, 47...Relatively short piston, 6
0.61.62...Guide piston, 68.64...
- Variable gas space section, 69... gas space. Patent applicant Aisin Seiki Co., Ltd. Representative Reio Nakai Yoshihiro Ishizaki

Claims (1)

[Scope of Claims] l) Two relatively long pistons with guide pistons and one relatively short piston with guide pistons, and a number of heat accumulators, heat exchangers, etc. In a gas engine consisting of one set or multiple sets constituting one heat cycle, the respective pistons and the piston reciprocating mechanism are connected via a guide piston, and a gas space for removing oil is provided, and A Stirling cycle engine is characterized in that a variable gas space is provided between a relatively long piston and a rod seal, and the same fluid as the working fluid is introduced into the variable gas space. 2) Two relatively long pistons with guide pistons, one relatively short piston with guide pistons, and a large number of heat accumulators, heat exchangers, etc.
) In a gas engine consisting of one set or multiple sets constituting a thermal cycle, a part of the working fluid is sucked into the piston, discharged from the piston, or sucked into the portion of the relatively long piston that faces the rod seal. , a Stirling cycle engine featuring a mechanism for discharging air. 8) A set of two relatively long pistons with guide pistons and one relatively short piston with guide pistons each, and a number of heat storage devices, heat exchangers, etc., constituting two heat cycles, or In a gas engine consisting of a large number of sets, the variable gas space formed between the relatively long piston and the rod seal is operated at approximately the intermediate pressure or lower pressure of the working fluid whose pressure fluctuates in the expansion section and the compression section. A Stirling cycle engine is characterized by the fact that the engine is operated by guiding fluid. 4) A set of two relatively long pistons with guide pistons, one relatively short piston with guide pistons, each cylinder, and a number of heat accumulators, heat exchangers, etc., forming two heat cycles, or In a gas engine consisting of multiple sets, the relatively long piston is connected to a piston cap and seal ring filled with a thin, multi-perforated metal or ceramic plate and a heat insulating material, and a valve connecting the fluid sealing valve and the piston rod. A Stirling cycle engine characterized in that it is constructed and used by connecting a piston element part containing a structure part with a large number of bolts. 5) A set of two relatively long pistons with guide pistons and one relatively short piston with guide pistons each, and a number of heat storage units, heat exchangers, etc., forming two heat cycles, or In a gas engine consisting of multiple sets, a part of the relatively short piston cylinder is reconfigured into a compressor, and the working fluid here is sucked in from within the crankcase, oil separated, and pressurized to a variable volume space. 6) Two relatively long pistons with guide pistons and one relatively short piston with guide pistons. Comparison of two comparatively long pistons with guide pistons and one with guide pistons in a gas engine consisting of one set or multiple sets of cylinders and a number of heat storage devices, heat exchangers, etc., forming two heat cycles. short piston 1
Two heat cycles are constructed by each cylinder of the book, as well as a large number of heat storage units, heat exchangers, etc.A set of T gas engines is combined, each short piston is placed at both ends of the crankshaft, and a long piston with a guide piston is also installed. A Stirling cycle engine characterized by a bank angle of approximately 45 degrees.