JP2624252B2 - Oil rising prevention device of Stirling engine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a Stirling engine oil that prevents oil lubricating a drive mechanism from entering a compression chamber of a crankcase pressurizing Stirling engine. The present invention relates to a rising prevention device.

[Conventional technology]

FIG. 4 shows an example of a conventional oil rising prevention device using an oil seal. In the figure, reference numeral 30 denotes a crankcase, and the lower structure of the crankcase is omitted. 1 is a cylinder liner on which the power piston 8 and the crosshead 5 slide, 2 is a piston ring mounted on the power piston 8,
3 is a partition wall for an oil seal on which an oil seal 4 is mounted.
5 is a crosshead to which a power piston 8 is fixed, 6 is a connecting rod for vertically moving the crosshead 5, 7 is a piston pin connecting the crosshead 5 and the connecting rod 6, 8
Is a power piston, 9 is a piston rod that is integral with the crosshead 5 and supports the power piston 8, 10 is a compression chamber in the upper space of the power piston 8, 11 is a distance chamber in a lower space of the power piston 8, and 12 is a cross chamber of the crosshead 5. This is a buffer room in the lower space.

In the Stirling engine having such a configuration, the sliding surface of the crosshead 5 with the cylinder liner 1 is lubricated with oil, so that the oil that has risen above the crosshead 5 is scattered and rises into the upper space. Most of the oil that has scattered and rises falls down against the oil seal partition 3, and the oil attached to the piston rod 9 is scraped off by the oil sheet 4.

However, the oil (about 60 ° C.) whose temperature has risen due to the movement of the crosshead 5 is partially vaporized and rises from the leakage gap of the oil seal 4, and the power piston 8 having a low temperature is formed.
In the space below the cylinder liner 1 (approximately 40 ° C.) and the power piston 8 and again form oil droplets. If this scatters to the low-temperature heat exchanger (cooler) or the regenerator, it contaminates the heat transfer surface thereof, significantly lowers the heat transfer coefficient, and causes abnormal friction and fluctuations in the pressure balance of the piston ring 2.

[Problems to be solved by the invention]

Since the conventional oil rising prevention device of a Stirling engine is configured as described above, when oil rising is prevented by an oil seal, the rise of steamed oil cannot be prevented. Therefore, to avoid this, it is necessary to use a low vapor pressure lubricating oil, but such a lubricating oil has a higher viscosity than ordinary lubricating oil, resulting in a large mechanical loss and a low lubricating oil price. There was a problem such as high.

The present invention has been made in view of such a point, and there is a stirling engine oil for preventing condensation of oil that has been turned into steam without using a low-vapor-pressure lubricating oil as described above. The purpose is to obtain.

[Means for solving the problem]

The oil rising prevention device for a Stirling engine according to the present invention is provided with temperature adjusting means for adjusting the temperature of the distance chamber below the power piston and the temperature of the cylinder liner of the sliding portion of the power piston to the same temperature as the lubricating oil. .

[Action]

In the present invention, since the distance chamber and the cylinder liner are maintained at the same temperature as the lubricating oil by the temperature adjusting means, the oil which has become steam is not condensed in the distance chamber, etc. Thus, the oil is sealed by the piston ring of the power piston, and no liquid oil enters the working chamber.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an oil rising prevention device according to a first embodiment of the present invention. In the figure, components indicated by reference numerals 1 to 12 have exactly the same configuration as the configuration shown in FIG. twenty two
Is provided on the outer periphery of the cylinder liner 1, a temperature-regulated water flow path through which temperature-regulated water flows, 20 is a temperature-regulated water inlet into which the temperature-regulated water flows through the flow path 22, and 21 is a temperature-regulated water flowing out The temperature control water outlet 23 is a partition wall that forms the temperature control water flow path 12. Although not shown, the temperature adjustment water is controlled outside the cylinder to a required temperature.

 Next, the operation and effect will be described.

As described with reference to the example of FIG. 4, the lubricating oil whose temperature has increased due to the operation of the engine is partially vaporized and rises from the leakage clearance of the oil seal 4. When the lubricating oil temperature is high, the following operation
11 and raise the temperature of the cylinder liner 1. That is, hot water heated to a required temperature is caused to flow through the flow path 22, the cylinder 1 is first heated by the hot water, and the distance chamber 11 is warmed by the heated cylinder 1. Therefore, if the temperature of the hot water is adjusted, the temperature of the distance chamber 11 can be made equal to the temperature of the oil whose temperature has been increased, whereby the lubricating oil that has turned into steam can be removed from the inner wall of the distance chamber 11 cylinder liner 1. The distance chamber does not shrink
The oil vapor of 11 becomes a saturated vapor amount and equilibrates. Since this steam is sealed by the piston ring 2 of the power piston 8, it does not leak to the compression chamber 10 to an amount that adversely affects the Stirling engine.

Therefore, in this embodiment, the oil that has become steam does not lower the heat transfer performance of the low-temperature side heat exchanger (cooler) or the regenerator, and causes abnormal wear and pressure balance fluctuations on the piston ring 2. And the like can be solved.

Next, FIG. 2 shows an oil rising prevention device according to a second embodiment of the present invention. In the first embodiment, in order to adjust the temperature of the distance chamber 11, the temperature adjusting water is supplied to the outer periphery of the cylinder liner. In the second embodiment, the heater 24 is wound around the outer periphery of the cylinder 1. Thus, the cylinder 1 is electrically heated so that the distance chamber 11 is warmed, and this embodiment has the same effect as the above embodiment.

In the first and second embodiments, the case where the present invention is applied to a system in which oil rising is stopped by using an oil seal has been described. However, as shown in FIG. The temperature of the distance chamber 11 may be adjusted by flowing temperature-adjusted water to a system in which oil rising is stopped by the sponge 15 for use, and the same effect as in the first embodiment can be obtained.

Although not shown, an oil seal sponge may be used instead of the oil seal of the second embodiment, and the temperature of the distance chamber 11 may be adjusted by a heater.

In each of the above embodiments, the case where the present invention is applied to a Stirling engine has been described. However, the present invention can also be applied to a Stirling cycle refrigerator, a GM cycle refrigerator, a Bellmeier engine, a lubrication-free compressor, and the like. Also, the type of the Stirling engine (β displacer type, γ displacer type, double-acting type) is not specified.

〔The invention's effect〕

As described above, according to the oil rising prevention device for a Stirling engine according to the present invention, since the temperature adjusting means for adjusting the temperature of the cylinder liner of the distance chamber and the sliding portion of the power piston to the same temperature as the lubricating oil is provided, This has the effect of preventing condensation of oil vapor and preventing abnormal wear of the piston ring and fluctuations in pressure balance without deteriorating the heat transfer performance of the low-temperature side heat exchanger (cooler) and the regenerator.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an oil rising prevention device for a Stirling engine according to a first embodiment of the present invention. FIG. 2 is a sectional view showing an oil rising prevention device for a Stirling engine according to a second embodiment of the present invention. FIG. 3 is a sectional view showing an oil rising prevention device for a Stirling engine according to a third embodiment of the present invention, and FIG. 4 is a sectional view showing a conventional oil rising prevention device for a Stirling engine. In the drawing, 1 is a cylinder liner, 2 is a piston ring, 3 is an oil seal partition, 4 is an oil seal, 5 is a crosshead, 6 is a connecting rod, 7 is a piston pin, 8
Is a power piston, 9 is a piston rod, 10 is a compression chamber, 11
Is a distance chamber, 12 is a buffer chamber, 15 is a sponge for oil seal, 20 is a temperature control water inlet, 21 is a temperature control water outlet, 22 is a temperature control water flow path, 23 is a partition, and 24 is a heater. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (3)

(57) [Claims] 1. A crosshead or piston rod and a power piston, a buffer chamber below the crosshead or piston rod, and a distance chamber between the crosshead or piston rod and the power piston. In the crankcase pressurizing type Stirling engine provided with the crosshead or the piston rod to be lubricated with oil, the lubricating oil of the Stirling engine is prevented from flowing into the working chamber of the Stirling engine. An oil rising prevention device for a Stirling engine, comprising: a temperature adjusting means for adjusting a temperature of a distance chamber below a power piston and a cylinder liner of a sliding portion of the power piston to a temperature equivalent to lubricating oil. apparatus. 2. A stirling engine oil stirrer according to claim 1, wherein said temperature adjusting means flows water for temperature adjustment through a flow path formed on the outer periphery of the cylinder liner. apparatus. 3. A stirling engine oil stirrer according to claim 1, wherein said temperature adjusting means is a heating coil or a bimetal for cooling wound around the outer periphery of the cylinder liner.