JP2541983B2 - Stirling engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Stirling engine, and more particularly to an output control mechanism that controls the output of the engine by increasing or decreasing the average pressure of the working space.

[Conventional technology]

FIG. 3 is a cross-sectional configuration diagram of a conventional Stirling engine as shown, for example, in "STIRLING ENGINE" by G. WALKER, OXFORD UNIVERSITY PRESS 1980. In the figure, 1 is a heater, 2 is a regenerator, 3 is a cooler, 4 is a high temperature side space, 5 is a low temperature side space, 6 is a reaction chamber,
Reference numeral 7 is a crank chamber, and 8 is a buffer chamber. Further, 17 is a crankshaft for taking out the output from the working spaces 4, 5, 27 is a compressor for reducing the average pressure of the working space and filling the buffer chamber 8 with working gas, and 28 is the average pressure of the working space. Control valve for adjustment, 29 is control valve
It is a slider in 28.

 Next, the operation will be described.

In the Stirling engine as shown in FIG. 3, the high temperature side space 4, the heater 1, the regenerator 2, the cooler 3, and the low temperature side space 5 are used.
The work of the working gas in the working space composed of is taken out by the crankshaft 17 as a rotating work. Since this work is proportional to the average pressure of the working gas in the working space, the output control controls the average pressure of the working space by the control valve 28.
Adjust according to.

That is, when the slider 29 in the control valve 28 is in the state shown in FIG. 3, the average pressure in the working space is constant. And if the slider 29 moves slightly to the left,
The working gas in the working space is filled in the buffer chamber 8 by the compressor 27, and the average pressure in the working space is reduced. When the slider 29 further moves to the left, the working space and reaction chamber 6
And communicate with each other and act as an unloader. When the slider 29 moves to the right, the working gas charged in the buffer chamber 8 is sent to the working space, and the average pressure is increased.

In this way, output control is performed by increasing or decreasing the average pressure of the working space.

[Problems to be solved by the invention]

Since the conventional Stirling engine is configured as described above, a compressor is required as an auxiliary machine for controlling the output of the engine, which causes a problem that extra power is required.

The present invention has been made in order to solve the above problems, and a Stirling engine capable of performing output control without consuming an extra power without requiring a compressor for engine output control. The purpose is to get.

[Means for solving problems]

The Stirling engine according to the present invention has a working space,
A reaction chamber and two buffer chambers for adjusting the average pressure of the reaction chamber, the reaction chamber and the working space are communicated with each other via a check valve that makes the working space the forward direction from the reaction chamber, The working space and each of the two buffer chambers are communicated with each other through a check valve for opening and closing the buffer chamber in the forward direction from the working space and an opening / closing valve, and an opening / closing valve provided at an inlet / outlet of each buffer chamber, And the two buffer chambers are communicated with each other through a check valve and an on-off valve that direct the reaction chamber from the buffer chamber to the forward direction, and an on-off valve provided at the inlet and outlet of each buffer chamber, and communicate with each other. An opening / closing valve for setting an initial state is provided in the common communication passage, and output control is performed by adjusting the average pressure of the working space and the reaction chamber by opening / closing each of the opening / closing valves.

[Action]

In this invention, since the reaction chamber and the working space are communicated so that the working gas flows from the reaction chamber to the working space, the lowest pressure of the gas pressure fluctuation in the working space is the highest pressure of the gas pressure fluctuation of the reaction chamber. Since the working space and the two buffer chambers are communicated with each other through the on-off valve so that the working gas flows from the working space to the buffer chamber, the above-mentioned on-off valve opens the inside of the working space. Since the working gas acts so as to be charged in the buffer chamber and the reaction chamber and the two buffer chambers are connected to each other through the on-off valve so that the working gas flows from the buffer chamber to the reaction chamber, the on-off valve should be opened. The working gas in the buffer chamber is charged to the reaction chamber by the operation of the engine, and the engine is operated by closing only the opening / closing valve for initial state setting. The pressure acts so that it becomes the minimum pressure of the fluctuation pressure of the operating space and the maximum pressure of the fluctuation pressure of the reaction chamber.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment in which the present invention is applied to a displacer type Stirling engine, in which 1 is a heater, 2 is a regenerator, 3 is a cooler, 4 is a high temperature side space, 5 is a low temperature side space, 6 is a reaction chamber, 7 is a crank chamber, 8a is a first buffer chamber, and 8b is a second buffer chamber. 9 is a displacer, 10 is a displacer rod connected to the displacer 9, 11 is a displacer connecting rod connected to the displacer rod 10, 12 is a power piston, 13 is a power piston rod connected to the power piston 12, 14 is a power piston rod A crosshead interlocking with the power piston 12 via 13, 15a and 15b are power piston connecting rods connected to the crosshead 14, 16 is a crankcase, 17 is a crank connected to the displacer connecting rod 11 and power piston connecting rods 15a and 15b. A shaft, 18 is a mechanical seal, and 19 is lubricating oil.

Further, 20 is a check valve that connects the low temperature side space 5 of the working space and the reaction chamber 6 and makes the low temperature side space 5 forward from the working chamber 6, and 21 is the low temperature side space 5 and the buffer chambers 8a, 8b. On-off valve 23,
25, 26, 30 communicate with each other, the low temperature side space 5 to the buffer chamber
A check valve 8a, 8b in the forward direction, 22 communicates the reaction chamber 6 with the buffer chambers 8a, 8b via the on-off valves 24, 25, 26, 30 and connects the reaction chamber 6 from the buffer chambers 8a, 8b. This is a check valve that operates in the forward direction.

 Next, the operation will be described.

In the Stirling engine configured as described above, the check valve 20 causes the minimum pressure fluctuation of the working gas in the working space to be substantially equal to the maximum pressure fluctuation of the gas in the reaction chamber 6.

Now, the operating space constituted by the heater 1, the regenerator 2, the cooler 3, the high temperature side space 4, and the low temperature side space 5 has the highest average pressure (see FIG. 2 (a)), and the on-off valve 30 Is always in the "open" state.

When the on-off valves 23 and 25 are opened from this state, the gas in the working space flows into the first buffer chamber 8a, the average pressure in the working space decreases, and the pressure in the first buffer chamber 8a rises. Here, when at least one of the on-off valves 23 and 25 is closed, the average pressure in the working space is stable in the state at that time (see FIG. 2 (b)). When the open / close valves 23 and 25 are continuously opened, the maximum pressure of the working gas pressure fluctuation in the working space and the pressure in the first buffer chamber 8a become substantially equal (see FIG. 2 (c)), and the average pressure in the working space becomes It is in an intermediate state. At this time, the on-off valves 23 and 25 may be in either “open” or “closed” state.

Next, when the opening / closing valve 25 is closed and the opening / closing valves 23 and 26 are opened, the working gas in the working space flows into the second buffer chamber 8b, the average pressure in the working space drops, and the pressure in the second buffer chamber 8b rises. Here, when at least one of the on-off valves 23 and 26 is closed, the average pressure in the working space is stabilized in the state at that time (see FIG. 2 (d)). When the open / close valves 23 and 26 are continuously opened, the maximum pressure of the working gas pressure fluctuation in the working space becomes substantially equal to the pressure in the second buffer chamber 8b (see FIG. 2 (e)), and the average pressure in the working space becomes It becomes the lowest state. At this time, the on-off valves 23 and 26 may be in either “open” or “closed” state.

 Next, the case of increasing the pressure will be described.

When the on-off valves 23 and 25 are closed and the on-off valves 24 and 26 are opened from the state shown in FIG. 2 (e), the working gas in the second buffer chamber 8b flows into the reaction chamber 6 and the average of the reaction chamber 6 is reached. The pressure rises and the average pressure in the working space rises. Where the on-off valve 24
When at least one of 26 is closed, the average pressure in the working space is stabilized in the state at that time (see FIG. 2 (d)). When the open / close valves 24 and 26 are continuously opened, the minimum pressure fluctuation of the reaction chamber 6 and the pressure of the second buffer chamber 8b become substantially equal (see FIG. 2 (c)), and the average pressure of the working space is in the middle. It becomes a state. At this time, the on-off valves 24 and 26 may be in either “open” or “closed” state.

Next, when the on-off valve 26 is closed and the on-off valves 24 and 25 are opened, the first
The working gas in the buffer chamber 8a flows into the reaction chamber 6, the average pressure in the reaction chamber rises, and the average pressure in the working space rises. Here, when at least one of the on-off valves 24 and 25 is closed, the average pressure of the working space becomes stable in the state at that time (Fig. 2 (b)).
reference). Further, when the open / close valves 24 and 25 are continuously opened, the minimum pressure of the reaction chamber pressure fluctuation and the pressure of the first buffer chamber 8a become substantially equal (see FIG. 2 (a)), and the average pressure of the working space is the maximum pressure. It becomes the state of.

Next, the operation of the initial state setting open / close valve 30 will be described.

When the pressure in the working space, the reaction chamber 6, the crank chamber 7 and the two buffer chambers 8a, 8b is in any state, only the on-off valve 30 is closed,
When the on-off valves 23, 24, 25, 26 are opened and the engine is operated, the pressure in the first buffer chamber 8a is the highest of the fluctuating pressure of the working space, and the pressure of the second buffer chamber 8b is the lowest of the fluctuating pressure of the reaction chamber 6. It becomes equal to the pressure (see FIG. 2 (c)), the average pressure of the working space becomes an intermediate pressure state, and the working space and the reaction chamber 6
And the pressure states of the two buffer chambers 8a and 8b are set to the pressure states during the steady operation.

By controlling the opening / closing valves 23 to 26, 30 to open / close in this manner, the average pressure in the working space, that is, the output of the engine can be adjusted to a wide range.

In addition, although the case where the present invention is applied to the displacer type Stirling engine has been described in the above embodiment,
The present invention applies to other types of Stirling engines, such as two
It may be applied to a piston type Stirling engine, a double acting type Stirling engine, etc., and has the same effect as the above-mentioned embodiment.

Further, although the above embodiment shows the case where there are two buffer chambers, the number of buffer chambers may be more than that, and the more the buffer chambers are, the larger the variable width of the average pressure of the working space, that is, the control width of the engine output, and the similar effect. Play.

Further, in the present invention, the case where the on-off valve for the initial setting is provided has been described, but in an engine in which the pressure states of the respective working spaces, reaction chambers and buffer chambers are initially set, this on-off valve is not necessary. The same effect as the present invention can be obtained.

〔The invention's effect〕

As described above, according to the present invention, in the Stirling engine including the working space, the reaction chamber, and the two buffer chambers for adjusting the average pressure of these, the chambers are communicated with each other via the check valve. At the same time, an opening / closing valve is provided at each communication passage and the entrance / exit of each buffer chamber, and the output control is performed by adjusting the average pressure of the working space and the reaction chamber by the opening / closing control of each opening / closing valve. A compressor is no longer needed as an auxiliary machine for the machine, no extra power is required,
There is an effect that the engine output can be controlled to a large degree arbitrarily.

[Brief description of drawings]

FIG. 1 is a sectional configuration diagram showing a Stirling engine according to an embodiment of the present invention, FIG. 2 is a characteristic diagram for explaining its operation, and FIG. 3 is a sectional configuration diagram showing a conventional Stirling engine. 1 ... Heater, 2 ... Regenerator, 3 ... Cooler, 4 ... High temperature side space, 5 ... Low temperature side space, 6 ... Reaction chamber, 7 ... Crank chamber, 8 ... Buffer chamber, 12 ... … Power piston,
16 …… Crankcase, 17 …… Crankshaft, 20-22 ……
Check valve, 23-26,30 ... Open / close valve. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A working space for performing a Stirling cycle, a reaction chamber formed on a side opposite to the working space with respect to a power piston for obtaining an output from the working space, and an average pressure of the working space or the reaction chamber. A Stirling engine having a first buffer chamber and a second buffer chamber for adjusting the control chamber, wherein the reaction chamber and the working space are communicated from the reaction chamber through a check valve having the working space as a forward direction. The working space and the first and second buffer chambers include a check valve and an opening / closing valve that make the buffer chamber the forward direction from the working space, and a buffer chamber opening / closing valve provided at the inlet and outlet of each buffer chamber. The reaction chamber and the first and second buffer chambers are communicated with each other through a check valve and an opening / closing valve that direct the reaction chamber from the buffer chambers in the forward direction, and a buffer chamber provided at the inlet and outlet of each buffer chamber. Via the on-off valve for An opening / closing valve for setting an initial state is provided in a common communication passage that communicates with the working chamber, the reaction chamber, and the first and second buffer chambers, and controls the opening / closing of each of the opening / closing valves. A Stirling engine characterized by controlling the output of the engine by adjusting the average pressure of the space and the reaction chamber.