JPH04334748A - Stirling engine - Google Patents

Abstract

PURPOSE:To prevent engine overspeed immediately after starting an engine by starting it in the state where heating tube wall temperature is low at the time of hot starting (cylinder wall temperature is high). CONSTITUTION:Expansion room cylinder 2 wall temperature is detected by a temperature detector 7 connected to a heating tube 3, and a condition (heating tube wall temperature) to send a starting signal in accordance with this temperature. Consequently, it is possible to prevent engine overspeed immediately after starting by changing the condition to send the starting signal by way of detecting temperature of the expansion room cylinder wall.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starting control method for a Stirling engine.

0002

2. Description of the Related Art FIG. 2 shows a conventional Stirling engine. In the figure, 1 is a Stirling engine main body, 2 is an expansion chamber cylinder, 3 is a heat exchanger tube, 4 is a temperature detector for detecting the heat exchanger tube wall temperature, 5 is a starter device, and 6 is a combustor.

Next, the operation will be explained. Fuel (for example, city gas) is burned in the combustor 6, and the heat is transferred to the heat transfer tube 3.
The working gas (e.g. helium gas) inside the engine is heated through the engine. When the temperature detector 4 detecting the wall surface temperature of the heat transfer tube 3 detects a certain value (for example, 700° C.), the temperature detector 4 gives a signal to the engine starting device 5 to start the engine. The externally powered engine absorbs the heat of combustion and begins self-sustaining operation.

In a Stirling engine, the higher the temperature of the working gas in the expansion chamber, the higher the output. To ensure a smooth start, the engine is started with no load applied, and after the output reaches a certain level, it is operated with a load connected.

[0005]

[Problems to be Solved by the Invention] Since the conventional Stirling engine is configured as described above, the heat exchanger tube and expansion chamber cylinder can be started in a low temperature state (cold start) and in a high temperature state (hot start). If the heat exchanger tube wall temperature is set to the same temperature as that of the heat exchanger tube, the working gas in the expansion chamber is also high temperature during a hot start, so the engine will produce a large output from the time of startup, and immediately after startup the engine will overspeed (the engine speed is at the rated speed). There was a problem in that the rotation occurred at higher speeds. On the other hand, during a cold start, the heat transfer tube wall temperature rises and even if the engine is started, the engine rotation speed is low because the expansion chamber cylinder and working gas are low.

The present invention was made to solve the above-mentioned problems, and its object is to prevent overspeeding immediately after hot start.

[0007]

[Means for Solving the Problems] In the Stirling engine according to the present invention, the value of the heat transfer tube wall temperature, which is a starting signal, is changed depending on the expansion chamber cylinder wall temperature.

[0008]

[Operation] In this invention, by detecting the cylinder wall temperature, it is possible to detect whether the Stirling engine is in a hot start state or a cold start state. Start the engine.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1, 2, 3, 4, 5, and 6 indicate the same parts as in the conventional example, and 7 is a temperature detector that detects the temperature of both the wall of the heat exchanger tube 3 and the wall of the expansion cylinder 2. in,
It is connected to the starting device 5.

In the Stirling engine configured as described above, fuel is combusted in the combustor 6, and the heat is transferred to the working gas (not shown) inside the engine through the heat transfer tube 3.
heat up. When combustion starts in the combustion chamber 6, the heat transfer tube 3
is heated, and the temperature of the heat transfer tube wall increases. At this time, for example, if the expansion chamber cylinder 2 wall temperature is a low temperature (for example, 30°C) (an example of a cold start), the heat exchanger tube wall temperature is 70°C.
When the temperature reaches 0° C., the temperature detector 7 sends a signal to the starting device 5 to start the engine. On the other hand, when the expansion chamber cylinder wall temperature is high (e.g. 400°C) (example of hot start)
When the heat exchanger tube wall temperature reaches, for example, 500° C. (lower temperature than at the cold start), the temperature detector 7 sends a signal to the starting device 5 to start the engine.

[0011]

[Effects of the Invention] As described above, according to the present invention, when the expansion chamber cylinder wall temperature is high, the engine start signal is issued at a heat exchanger tube temperature lower than that at a cold start, so that the engine output at the time of start can be adjusted appropriately. This can prevent engine overspeed immediately after startup.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a Stirling engine according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional Stirling engine.

[Explanation of symbols]

1 Stirling engine body 2
Expansion chamber cylinder 3 Heat transfer tube 5 Starting device 6 Combustor 7 Temperature detector

Claims (1)

[Claims] Claim 1: In a Stirling engine equipped with a temperature detector that detects the temperature of the heat transfer tube wall of the combustor section, which serves as a starting signal, the temperature sensor also detects the cylinder wall temperature, and the starting signal is determined based on this cylinder wall temperature. A Stirling engine characterized by changing the value of the heat transfer tube wall temperature, which serves as a signal.