JPS62107281A - Reciprocating compressor for oilless compression of gas - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention A. Field of Industrial Application The present invention relates to a reciprocating compressor for oil-less compression of gas, which comprises at least one piston that is reciprocatable by a crankshaft and a stove r in a cylinder. Regarding reciprocating compressors that have.

BACKGROUND OF THE INVENTION Conventional reciprocating compressors for this purpose are of the cross-head type - that is, the rotor P is connected to the crankshaft, the piston is connected to the piston by a piston rod, and is pivotally connected to the cross-head pin. Therefore, it is a crosshead type in which the piston rod reciprocates linearly with the piston. The crankshaft, connecting rods, and crosshead are oil-lubricated parts of the drive, and an intermediate member known as a lantern ring prevents lubricating oil from entering the cylinder. It is separated from the cylinder by an intermediate member serving as Because of the crosshead and piston rod, this type of reciprocating compressor occupies a relatively large amount of space. Furthermore, construction costs are relatively high.

Problems that the Invention Attempts to Solve The described reciprocating compressor for crops is cheaper to construct than prior art devices and takes up relatively less space than prior art devices. It is an object of the present invention to provide a reciprocating compressor that blocks the

According to the present invention, the connecting rod is directly pivoted to the piston, the piston portion near the compression chamber is an oil-free gas seal portion, and the connecting rod portion near the crankshaft is a non-lubricated gas seal portion. A lubricated guide part sliding in the cylinder, an oil scraping device being provided in the reciprocating area of the guide part and connected by at least one conduit to the low pressure chamber and to the compression chamber. A line is connected to the cylinder wall in the area between the oil scraper and the gas seal, which is effective for removing leaking gas from the crankcase and oil leaking from the crankcase.

Pivoting the connecting rod directly to the piston results in a cylindrical piston type compressor--that is, a compressor that lacks a crosshead and a piston rod that reciprocates linearly with the piston.

Since the piston has a non-lubricated gas seal section and a lubricated guide section, the overall length of the piston is longer than in the case of a conventional lubricated cylindrical piston, but the compressor The cost of construction and the space it occupies is less than in the case of a crosshead compressor compressing without lubrication. The oil scraper and the leakage gas and N leakage drain lines ensure that lubricating oil never passes from the lubricated area of the piston to its unlubricated area. Thus, the advantages of a cylindrical piston type compressor are combined with those of an oil-free crosshead type compressor, whereas the disadvantages of the latter type of compressor are eliminated.

E. Embodiments and Operations Specific examples of the present invention will be described in detail with reference to the drawings, which are in schematic form.

Referring to FIG. 1, the compression device has a crankcase 1 in which a crankshaft 2 is mounted and a connecting rod 4 pivotally connected to a crankbin 3 of the crankshaft 2. Referring to FIG.

A cylinder 5 , the centerline 6 of which extends substantially horizontally, is connected to the crankcase 1 . A cylinder head T is arranged at the end of the cylinder 5 remote from the crankcase 1, the cylinder head 7 having an inlet line 8 for the gas to be compressed and an outlet for the compressed gas. and a conduit 9. The cylinder head 7 has an inlet valve 10 and an outlet valve 11 engaged with conduits 8, 9, respectively.
It further contains.

The piston 12 is arranged in the cylinder 5 and the connecting rod 4 is connected directly by a rad pin 13 to the connecting rod in engagement with the crankcase 1 to a section 12' crosswise. Therefore, and as is known in the cylindrical piston structure, the crank drive mechanism 2~
4 directly - i.e. without the intervention of a crosshead and without the intervention of a piston rod between the crosshead pistons,
Piston 12fc is driven. The connecting rod section 12' is in the form of a guide section which substantially contacts the wall of the cylinder 5 as it reciprocates. Part 12' is lubricated, for example, by oil passing from crankcase 1 to cylinder 5. The connecting rod section 12' has two rings 14 in an annular groove which act as oil scrapers, engaging the cylinder wall and ensuring that most of the oil entering the cylinder 5 returns to the crankcase 1. Two rings 14 are received.

Near the cylinder head T, a labyrinth sealing groove is provided in the piston part 12', which results in the formation of a contactless seal with the cylinder wall around the periphery of the piston part 12'. Piston portion 12 having within the circumference of portion 12'
' is formed.

A compression chamber 15 is arranged between the cylinder head and the piston part 12', which acts as a gas sealing part.

A region in which the end of the labyrinth seal portion of the piston portion 12' is located at its bottom dead center position with respect to the piston 12, i.e., at its bottom dead center position on the left side in FIG. In the area where the end close to the crankcase 1 is located, the cylinder 5 has an annular groove 17 and a conduit 16 leading to it.
An annular groove 17 is formed in which the two are connected.

Pipe 16 is a compression chamber 1 for leaking gas passing through the labyrinth seal.
This is effective in draining leaked oil that has not been returned to the crankcase by the oil scraper ring 14. For this purpose, the line 16 is connected to a chamber at a much lower pressure than the pressure in the annular groove 11. Further, a pressure equalizing pipe 18 extending to the crankcase 1 is connected to the annular groove 17. The described device therefore allows a cylindrical piston compressor to be used for oil-free compression of gases. Thanks to the line 16, the lubricating oil from the crankcase 1 cannot reach the labyrinth seal, and, however, the piston part 12' moves regularly in the cylinder 5 without contact and without wear. things are made certain. The pressure equalization line 18 offers the advantage that there are no pressure gradients on the oil scraper ring 14 and therefore piston speeds can be high without wear on the piston portion 12'.

According to FIG. 2, the oil scraper ring 14
2, on the cylinder 5, at the end of which an annular member 19 is received in an annular groove 17 and on the inside thereof a connecting rod part 12' which is a guiding member. Two engaged oil scrubbing rings 1
4f: Disposed firmly on the supporting cylinder 5. Leakage gas and oil can reach conduit 16 through holes (not shown) in annular member 19 .

Otherwise, the construction of the compressor is as described in FIG. 1, except that there is no line corresponding to pressure equalization line 18.

The embodiment shown in FIG. 6 is such that the oil scraper ring 14 is arranged in the stove part 12', which is the guide part of the piston, as in FIG. In the embodiment shown, the piston section 12' has a larger diameter than the connecting rod section 12'. The diameter of the cylinder 5 in the region of movement of the piston part 12' is correspondingly larger. Annular groove 1
7 and the discharge line 16 are arranged in the cylinder 5 at the step from the smaller diameter to the larger diameter.

In the embodiment shown in FIG. 4, the oil scraper ring 14 is again placed within the guide portion 12' of the piston, however, the piston portion 12' is instead formed with a labyrinth groove. It has two seal rings 20 made of a self-lubricating material such as Teflon or graphite. Additionally, in this example, the piston section 12'', which is the gas compression section, therefore drains any leaking oil through the ring 14 through the line 16 so that it comes into contact with the lubricating oil originating from the crankcase. There isn't.

In the device shown in FIG. 5, the structure of the crankcase 1 and the structures of the crank drive mechanisms 2 to 4 are the same as those shown in FIG. Guide part 1 of piston 12
2' is like that shown in FIG. Piston part 12
' is the shape of the labyrinth piston t, which has a larger diameter than the guide portion 12', as shown in FIG.
-I am doing it. In addition to the ring 4, the cylinder 5 is provided with a restrictor ring 2 of known construction and arranged between the piston part 12' and the oil shovel ring 14.
I have 1. The restrictor ring 21 is effective in reducing pulsations acting on the oil scraper ring 14. The reason for such pulsation is that the pressure acting in the chamber 22 between the oil scraper ring 14 and the end of the labyrinth part 12', which is also the piston part near the crankcase 1, is caused by the pressure acting during the intake stroke and the delivery stroke. This means that the pressure that acts between the two is different. A conduit 23 is connected to the chamber 22 which extends to a compensating vessel 24 in order to compensate these pulsations in a balanced manner.

Referring to FIG. 6, the guide portion 1 of the piston 12 is divided into two axially successive sealing stages while the smaller, single diameter labyrinth piston portion 12' is divided into two axially successive sealing stages.
2' has an oil scrubbing ring 14. The piston in question is, for example, the last piston of a multistage compression device. Between the two sealing stages, the cylinder 5 forms an annular groove 25 to which a conduit 26 is connected. At an intermediate pressure of the compressed gas via line 26, such intermediate pressure is drawn from the lower stages of the device to slow the overall pressure drop gradient acting on the piston 12. is injected to do so.

Effects of the Invention As a modification of the specific example described, an oil scraper ring 14
The number may be more or less than two. Furthermore,
The pressure equalizing pipe 18 is shown in FIGS.
It may also be used in the embodiments shown in the figures. In order to improve the oil scraping action of the oil scraper ring 14, the guide portion 12 is provided in a region within the region.
The cylinder 5 can be water-cooled in the region where ' is moving.

The present invention is equally useful for compressors in which the centerline of the cylinder is vertical.

[Brief explanation of drawings]

FIG. 1 shows a device containing a reciprocating compressor according to the invention, FIGS. 2 to 4 show another form of piston with cylinder, and FIG. 5 shows another variant of the compressor. FIG. 6 shows a piston and cylinder for two-stage sealing. In the figure, 1...crank case, 2...crankshaft,
4... stove top, 5... cylinder, 12...
Piston, 12'... connecting rod part (guide part L1
2'... Piston part (gas seal part), 14...
・Oil scraping device, 15...compression chamber.

Claims (6)

[Claims] (1) A reciprocating compressor for oil-less compression of gas, which has at least one piston that can be reciprocated by a crankshaft and a connecting rod in a cylinder, in which the connecting rod directly connects to the piston. The piston part near the compression chamber is the oil-free gas seal part, and the connecting rod part near the crankshaft is the lubricated guide part that slides inside the cylinder. At least one pipe installed in the reciprocating area of the guide part and connected to the low pressure chamber in the form of at least one pipe and effective for removing leaking gas from the compression chamber and leaking oil from the crankcase. A reciprocating compressor for oilless compression of gas, characterized in that a passage is connected to the cylinder wall in the area between the oil scraper and the gas seal part. (2) Oil-less compression of gas in the reciprocating compressor according to claim 1, characterized in that the pressure equalizing pipe extending to the crankcase is connected near the discharge pipe. Reciprocating compressor for. (3) A reciprocating compressor for oil-less compression of gas in the compressor according to claim 1 or 2, characterized in that the gas seal portion of the piston is formed with a labyrinth groove. compressor. (4) In the compressor according to any one of claims 1 to 6, the oil scraping device is fixed to the cylinder wall and is in contact with the guide portion of the piston. A reciprocating compressor for oilless compression of gas. (5) In the compressor according to any of claims 1 to 4, a restrictor ring is disposed in the cylinder and is arranged around the piston between the piston portion and the oil scraper ring. A reciprocating compressor for oilless compression of gas, which is characterized by being stretched. (6) In the compressor according to any of claims 1 to 5, the gas sealing portion of the piston is compressed to an intermediate pressure during at least two sealing stages. A reciprocating compressor for oil-less compression of gas, characterized in that the gas is further divided into at least two seal stages.