JPH0156279B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling piston compressor.

In general, rolling piston type compressors perform one compression operation per rotation of the piston, but when the rotation speed is high and the compression ratio is high, during this compression operation process, the piston passes through the exhaust port. , the high-pressure chamber and low-pressure chamber of the cylinder communicate instantaneously, and a shock wave is generated in the low-pressure chamber, just as when a diaphragm separating the high-pressure side and low-pressure side of a shock wave tube suddenly ruptures, and the pressure pulsations are transmitted to the cylinder. This caused the compressor, such as the piston, to vibrate, causing a sudden increase in the noise level.

In view of the above problems, this invention provides a dipping groove in the inner peripheral wall of the cylinder and gradually communicates the high pressure chamber and the low pressure chamber through the groove, thereby reducing the strength of shock waves and causing pressure pulsation. The purpose is to make it smaller.

The present invention will be described below with reference to embodiments shown in the drawings. As shown in FIGS. 1 and 2, a cylinder 1 includes a crankshaft 2 driven by an interlocking device or an engine (not shown), A piston 3 eccentrically rotates while abutting against the inner circumferential wall of the cylinder 1 by the crankshaft 2, and a vane groove 4 formed in the circumferential wall of the cylinder 1 so as to follow the rotation of the piston 3 and always abut against the outer circumferential wall.
A vane 5 that slides back and forth inside is installed.
Furthermore, a main bearing plate 6a and a sub-bearing plate 6b that support the crankshaft 2 are attached to both end surfaces of the cylinder 1. A gas exhaust port 7 is formed in one of these receiving plates, and a gas inlet port 8 is formed in the peripheral wall of the cylinder 1. Configure. These gas exhaust ports 7 and gas intake ports 8
is in communication with the inside of the cylinder 1, and since the vane 5 is always in contact with the outer circumferential wall of the piston 3, the inside of the cylinder 1 has a high pressure chamber 9a that can freely communicate with the gas exhaust port 7, and a gas intake port 8. and a low pressure chamber 9b which can freely communicate with each other.

In the inner circumferential wall of the high pressure chamber 9a of the cylinder 1, a dipping groove 10 is formed, as also shown in FIG. This groove 10 extends from the center of the opening surface of the gas exhaust port 7 in the counter-rotational direction of the piston 3, that is, in the clockwise direction in the drawing, and the length between both ends of the groove 10 is Set within a range of 1 to 4 times the diameter or equivalent diameter of the exhaust port (cross-sectional area of the gas exhaust port/4 times the circumferential length at the opening surface of the gas exhaust port) from the center of the exhaust port 7. be done.

Further, the maximum depth of the bridging groove 10 is set to about 5 to 25% of the diameter or equivalent diameter of the gas exhaust port 7.

Note that this bridging groove 10 is formed at a position that does not communicate with the gas exhaust port 7.

In the figure, reference numeral 11 is an exhaust valve that opens and closes the gas exhaust port 7, and is designed to open when the gas in the cylinder 1 exceeds the exhaust pressure.

Here, to describe the operation of the compressor with such a configuration, gas flowing into the low pressure chamber 9b from the gas intake port 8 is compressed by the piston 3 rotating counterclockwise inside the cylinder 1, and gradually When the high-pressure gas becomes higher than the exhaust pressure in the high-pressure chamber 9a, the exhaust valve 11 opens and the gas is exhausted from the high-pressure chamber 9a. By the way, as mentioned above, the high pressure chamber 9a is formed with the dipping groove 10, so that the high pressure chamber 9a and the low pressure chamber 9b are in communication with each other before the piston 3 reaches the center of the exhaust port 7. Therefore, the high pressure gas gradually enters the low pressure chamber 9b,
The intensity of the generated shock wave is reduced as if the diaphragm between the high pressure side and the low pressure side of the shock wave tube were slowly torn.

By the way, the length of this bridging groove 10 in the rotational direction of the piston 3, that is, the range that communicates the high pressure chamber 9a and the low pressure chamber 9b,
If it is made too large, the high pressure chamber 9a will be damaged by the low pressure chamber 9.
Since the leakage of gas to b rapidly increases, the essential compression performance deteriorates. Mata Nigashi Groove 1
It was inferred that there is no effect if the depth of 0 is too shallow or too deep, and that there is an optimal range. Therefore, when various shapes of the bittering grooves 10 were changed and experimentally investigated, the above-mentioned results were obtained. It has become clear that within that range, noise can be reduced with almost no deterioration in performance.

In addition, when the bittering groove 10 extends beyond the center of the gas exhaust port 7 in the rotational direction of the piston 3, the change in depth beyond the center has almost no effect on noise caused by shock waves or on performance. I also understood that.

FIG. 4 shows a comparison of the noise level with the conventional example. In the conventional example, the noise level is in the range A, and in the present invention, it is in the range B. Here, the vertical axis shows the noise level N, and the horizontal axis shows the rotation speed rpm of the compressor.

Figure 5 shows the pressure waveform inside the high pressure chamber.
Figure a shows an example of the present invention, and Figure b shows a conventional example. Compared to the conventional example, pressure pulsations are reduced by nearly half in the frequency range of 1 KHz or higher. Here, the vertical axis indicates the high pressure chamber pressure p, and the horizontal axis indicates the crank angle θ.

FIG. 6 is an example showing the relationship between the compression ratio and the noise level, where A shows the conventional example and B shows the present invention.The higher the compression ratio, the greater the noise reduction effect compared to the conventional example. Here, the vertical axis shows the noise level N, and the horizontal axis shows the compression ratio r.

As described above, in the present invention, the inner peripheral wall of the cylinder extends in the counter-rotation direction of the piston than the exhaust port,
and provide a groove that does not communicate with the exhaust port,
The length between both ends of this groove is set within a range of 1 to 4 times the diameter or equivalent diameter of the exhaust port from the center of the opening surface of the exhaust port, and its maximum depth is set to a range of 1 to 4 times the diameter or equivalent diameter of the exhaust port 5 to the diameter of the mouth or equivalent diameter
Since the configuration is set to a range of 25%, when the piston passes through the gas exhaust port, the high pressure chamber and low pressure chamber are in communication, and the high pressure gas gradually enters the low pressure chamber, so it instantly Strong shock waves are not generated in the low-pressure chamber, unlike when both chambers communicate. Therefore, pressure pulsations are also small, and the noise level can be reduced without deteriorating performance.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a compressor according to the present invention, and FIG.
The figure is a sectional view taken along the line A-A in Figure 1, Figure 3 is a perspective view showing the main parts of Figure 1, Figure 4 is a graph showing the relationship between the rotation speed of the compressor and the noise level, Figure 5 shows the pressure waveform in the high pressure chamber, Figure a is a graph showing an example of this invention, Figure b is a graph showing a conventional example, and Figure 6 is a graph showing the relationship between compression ratio and noise level. . DESCRIPTION OF SYMBOLS 1...Cylinder, 1a...Cylinder body, 3...Piston, 5...Vane, 7...Gas exhaust port, 8...Gas intake port, 9a...High pressure chamber, 9b...Low pressure chamber, 10...Rip groove. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1 A cylinder body having a gas intake port, a bearing plate having a gas exhaust port, a piston that rotates eccentrically while contacting the inner circumferential wall of the cylinder constituting the cylinder body, and a cylinder body that abuts the outer circumferential wall of the piston and rotates eccentrically inside the cylinder. In a rolling piston compressor, the rolling piston compressor has a vane that partitions into a low pressure chamber that can freely communicate with the gas intake port and a high pressure chamber that can freely communicate with the gas exhaust port. A groove not communicating with the exhaust port is provided, which extends in the counter-rotation direction of the groove, and the length between both ends of the groove is equal to or equal to the diameter of the exhaust port from the center of the opening surface of the exhaust port. More than 1 times the diameter 4
A rolling piston type compressor, characterized in that the maximum depth is set in a range of 5 to 25% of the diameter or equivalent diameter of the exhaust port.