JP2732484B2 - Oil-cooled screw compressor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an oil-cooled screw compressor provided with an oil separator and a reserve tank.

(Prior Art) Conventionally, as shown in FIG.
An oil-cooled screw compressor formed by assembling the motor 2 and the motor 33 together in one unit while separately providing a reserve tank 34 is known.

Then, the driving pulley 35, the driven pulley 36,
The compressed air sucked by the compressor body 31 driven via the belt 37 is compressed and discharged to the oil tank 32 together with the lubricating oil, where the lubricating oil is separated into gas and liquid through an oil separating element (not shown). While the oil is dropped into an oil reservoir 38 at the lower portion of the oil tank 32, the air is cooled by an aftercooler (not shown), and then temporarily stored in a reserve tank 34 and sent out therefrom.

After the lubricating oil in the oil sump 38 is cooled by an oil cooler (not shown), the lubricating oil is again sent to a lubricating oil supply point in the compressor main body 31 and used for circulation.

Here, since the oil tank 32 and the reserve tank 34 cannot be made very small in function, the specific gravity of the space occupied in the entire apparatus is considerably large, and as described above, the compressor body 31, the oil tank 32, and the motor 33 Are combined into one unit, but the reserve tank 34 is provided separately. That is, the oil tank 32 needs to have a height at which the oil reservoir 38 and the above-mentioned oil separation element (not shown) thereabove can be appropriately separated in order to efficiently perform gas-liquid separation. It is necessary to secure an amount of lubricating oil necessary for continuing circulation in the oil sump 38. Further, the reserve tank 34 has a size that allows the apparatus to operate efficiently and that the compressed air can be smoothly supplied.

(Problems to be Solved by the Invention) In general, when designing a machine, it is important to not only satisfy the requirements for the performance of the device but also how to make the entire device compact. In particular, due to the recent rise in land prices, demands for users of screw compressors for minimizing installation space for devices have been increasing.

However, in the conventional screw compressor described above, the reserve tank 34 is provided separately, and this occupies a considerable amount of space. Such space problems are greater in larger cities.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide an oil-cooled screw compressor capable of making the apparatus compact.

(Means for Solving the Problems) In order to solve the above problems, the first invention separates an oil component from a discharge gas and stores the separated oil in a discharge flow path connected to a discharge port of a compressor body. Oil separator and oil separated,
In an oil-cooled screw compressor provided with a reserve tank for storing cooled discharge gas, the above-mentioned oil separator and the above-mentioned reserve tank were formed in one container via a partition plate below the oil separator.

In the second invention, the partition plate is formed in an arched cross section, and the arched portion is an oil reservoir.

In the third invention, the partition plate in the second invention is formed such that the partition plate has an upwardly convex surface.

(Effect) By forming as in the first invention, not only the whole device becomes compact, but also the oil in the oil tank is cooled by the gas in the reserve tank.

Further, by forming like the second invention, in addition to the function of the first invention, the pressure resistance of the partition plate is improved with the same plate thickness as compared with the case of the flat plate, and the horizontal portion of the oil portion in the oil tank is improved. The cross-sectional area increases as it goes upward, and the rise in oil level due to foaming in the oil tank decreases.

Further, by forming the partition plate as in the third aspect, in addition to the operation of the second aspect, the pressure resistance of the partition plate is further improved as compared with the case of a flat plate or a downward convex surface with the same plate thickness.

(Example) Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows an oil-cooled screw compressor according to the first invention, in which a suction filter 5, an intake control valve 6, and a compressor main body 1, a motor 2 and a suction flow path 4 leading to a suction port 3 of the compressor main body 1. An oil separator 10, an aftercooler 11, and a reserve tank 12 are provided in a suction channel 7 and a discharge channel 9 following a discharge port 8 of the compressor body 1, and an oil filter is provided in a lubricating oil circulation channel 13.
14, a three-way switching valve 15 and an oil cooler 16 are provided.

The screw compressor main body 1 is fixed to a suction casing 7 and includes a pair of male and female screw rotors 17 meshing with each other rotatably supported by a discharge side bearing (not shown) and a suction side bearing in the suction casing 7. Housed,
Motor 2 through a driving pulley 18, a driven pulley 19, and a belt 20
Can be driven. Also, the suction casing 7
The suction control valve 6 is fixed to the suction control valve 6, and the suction filter 5 is fixed to the suction control valve 6, so that the suction passage 4 is formed by the communication space inside each.

An oil separator 10 and a reserve tank 12 below the oil separator 10 via a partition plate 21 are formed by one container. In addition, the mounting table 22 is erected around the oil separator 10 and the oil separator
An inlet 23 penetrating through the center of the upper surface of the upper surface 10 is formed, and the suction casing 7 is fixed on the mounting table 22 to support the compressor body 1 in a cantilever state. The discharge port 8 is formed so as to be pressed against and adhered to the inflow port 23 in a state in which the discharge port 8 is shut off from the outside. Further, an oil separation unit 25 is erected above a peripheral portion of the oil separator 10 opposite to the mounting table 22, and an oil separation element 26 is provided above a space in the oil separation unit 25. Take Exit 8
A discharge passage 9 extending from the oil separation element 26 to the aftercooler 11 and the reserve tank 12 via the pressure-retaining check valve 27 is formed. In the figure, the discharge flow path 9 is partially omitted, and the * marks communicate with each other.

The upper surface of the oil separation unit 25 is formed to have a predetermined height with respect to the upper surface of the mounting table 22, and the suction casing 7 and the intake control valve 6 are also formed to have predetermined heights, respectively.
By simply stacking and fixing the suction casing 7 and the intake control valve 6 on the mounting table 22, the upper surface of the intake control valve 6 and the oil separation section 25 are fixed.
The motor 2 is fixed on both upper surfaces via a support plate 28.

The lubricating oil circulation passage 13 exits the oil reservoir 29 at the lower part of the oil separator 10 and reaches an oil supply point such as a bearing in the compressor body 1, the suction casing 7 and a shaft seal.

Next, an operation state of the device having the above configuration will be described.

Drive pulley 18, driven pulley 19, belt 20 by motor 2
When the screw rotor 17 is driven to rotate through the air, the air sucked by the screw rotor 17 through the suction filter 5 is sucked from the suction port 3 through the suction flow path 4 and is compressed.
The oil is discharged to the discharge port 8 together with the lubricating oil supplied to the bearing and the like. The compressed air discharged together with the lubricating oil enters the oil separator 10 in the discharge passage 9, is separated into gas and liquid by the oil separating element 26, and the lubricating oil is dropped and temporarily stored in the oil reservoir 29. The compressed air separated from the oil reaches the aftercooler 11, where it is cooled by air from a fan (not shown), temporarily stored in a reserve tank 12, and then sent out of the machine as required.

On the other hand, the lubricating oil in the oil sump portion 29 reaches the oil cooler 16 via the oil filter 14 and the three-way switching valve 15, where it is cooled by air from a fan (not shown), like the compressed air in the aftercooler 11. After being sent to the oiling point in the compressor body 1 and the suction casing 7, the oil is collected in an oil sump 29,
Thereafter, it is used for circulation as described above. When it is not necessary to pass the oil cooler 16, such as when the temperature of the oil in the oil sump 29 does not need to be cooled, by switching the flow path of the three-way switching valve 15, the oil is filtered by the oil filter. The oil cooler 16 is formed to bypass the oil cooler 16 so that the oil can be directly sent to the oil supply point.

Here, since the oil separator 10 and the reserve tank 12 are formed by a single container, the entire apparatus is compactly assembled, and the lubricating oil in the oil reservoir 29 is cooled through the partition plate 21 in the reserve tank 12. So that the lubricating oil is also cooled by the cooled air.

Further, for example, when the compressor is started, bubbles are generated in the lubricating oil in the oil reservoir 29, and the oil level rises. On the other hand, in order to maintain the gas-liquid separation performance of the oil separation element 26, it is necessary to prevent the oil separation element 26 from being immersed in the lubricating oil even when the oil level rises. Can't be very close to it and needs to be separated to some extent. For this reason, the height of the conventional oil separator is increased and the whole is bulky, whereas in the present embodiment, the oil separator 10 is erected above the peripheral portion on one side of the oil separator 10. By providing the oil separation element 26 in the upper part of the space in the oil separation part 25, a sufficiently large distance is secured between the oil separation part 25 and the oil surface of the oil sump part 29 so that the other space can be effectively used. . That is, the portion of the oil separator 10 other than the oil separation unit 25 is reduced in height as a necessary minimum volume for storing the lubricating oil necessary for continuing to circulate the lubricating oil in the device, and this height is reduced. The compressor main body 1 is arranged in a space created by lowering the pressure, and the compressor main body 1 is located between the projecting portions of the oil separating portion 25, the suction casing 7, and the intake control valve 6. From the point of view, the whole apparatus is made compact.

Furthermore, the oil separator 10 has a shape with a reduced height and a larger cross section, except for the oil separator 25, so that when the center of the upper surface of the oil separator 10 is vibrated, it easily bends, and While a loud sound is likely to be produced by the same action, even if the peripheral portion is vibrated, it is hard to produce a sound because it is closer to a rigid body than the central portion. Therefore, in the present embodiment, the compressor body 1 which generates vibration and easily becomes a noise source is supported by the mounting table 22 via the suction casing 7 so as to receive the vibration around the oil separator 10 so that the oil separation is performed. The central part of the upper surface of the unit 10 is brought into contact with the compressor body 1 via an O-ring 24 to reduce noise.

In addition, the motor 2, which is likely to be a noise generating source, together with the compressor body 1 is mounted on the mounting table 2 via the support plate 28, the oil separation unit 25 and the support plate 28, the intake control valve 6, and the suction casing 7.
As described above, the vibration is propagated to the periphery of the oil separator 10 to reduce noise.

Preferably, the oil separator 10 is made of a thick material. In this case, as shown in FIG. 1, the oil separation element 26 can be easily provided in the horizontal direction, and the height of the oil separation portion 25 can be reduced. It is also possible to make the space lower and to make effective use of the space beside the oil separating section 25.

FIG. 2 shows an oil-cooled screw compressor according to a second invention, which is different from the apparatus shown in FIG.
Are substantially the same except for the point provided with, and corresponding parts are denoted by the same reference numerals and description thereof is omitted.

Here, the partition plate 21a has an arch-shaped cross section, and in this embodiment, is formed so as to have a downwardly convex surface.

When the screw compressor is stopped, while the pressure in the oil separator 10 is equal to the atmospheric pressure, while the high-pressure compressed air is stored in the reserve tank 12, the differential pressure on both sides of the partition plate 21a is large. In this case, the partition plate 21a has the same thickness and a higher pressure resistance than a flat plate. In other words, the partition plate 21a can withstand the same differential pressure, but can be made thinner than a flat plate.

Further, in the part of the partition plate 21a, the cross section becomes larger as going upward, and as described above, for example, even when a large amount of air bubbles are generated at the start of the apparatus and the oil level is going to rise, the oil level rises. At the same time, the area of the oil level increases, deaeration is promoted, and an increase in the oil level is suppressed.

FIG. 3 shows an oil-cooled screw compressor according to a third invention, which is substantially the same as the first invention except that a partition plate 21b is provided instead of the partition plate 21. Corresponding parts are denoted by the same reference numerals and description thereof is omitted.

Here, the partition plate 21b is formed in the shape of a cross-section arch having an upwardly convex surface.

And, compared to a flat plate or a partition plate having an arch-shaped cross section that becomes a downwardly convex surface, it can withstand greater pressure from below, and to withstand the same pressure, the plate thickness can be made the thinnest. I have.

In each of the first, second and third embodiments of the present invention, the compressed gas is air. However, the present invention is not limited to this. Including.

(Effects of the Invention) As is clear from the above description, according to the first invention,
The discharge passage connected to the discharge port of the compressor body includes an oil separator that separates oil from the discharge gas and stores the separated oil, and a reserve tank that stores the oil separated and cooled discharge gas. In the oil-cooled screw compressor, the oil separator and the reserve tank below the oil separator via a partition plate are formed in one container.

For this reason, in addition to being able to compact the whole apparatus, it is possible to cool the lubricating oil in the oil separator by the compressed air in the reserve tank.

Further, according to the second invention, the partition plate in the first invention is formed in an arch-shaped cross section, and the arch-shaped section is used as an oil reservoir. For this reason, in addition to the same effect as the first invention, the thickness of the partition plate that can withstand the differential pressure between the oil separator and the reserve tank can be made smaller than that of the flat plate, and the area of the cross section can be reduced. Are spread upward, so that degassing is promoted when the oil level rises due to the generation of bubbles in the lubricating oil, and the effect that the oil level rise can be suppressed is exerted.

Further, according to the third invention, the partition plate of the second invention is formed as an upwardly convex surface. For this reason, in addition to the same effect as the second invention, there is an effect that the thickness of the partition plate that can withstand the pressure received from the compressed gas in the reserve tank can be made thinner than a plate or a downwardly convex surface. Play.

[Brief description of the drawings]

1 is an overall configuration diagram of an oil-cooled screw compressor according to the first invention, FIG. 2 is an overall configuration diagram of an oil-cooled screw compressor according to the second invention, and FIG. 3 is an oil according to the third invention. FIG. 4 is an overall configuration diagram of a conventional oil-cooled screw compressor. 1 ... compressor body, 8 ... discharge port, 9 ... discharge flow path, 10
... oil separator, 11 ... aftercooler, 12 ... reserve tank, 21, 21a, 21b ... partition plate.

Claims (3)

(57) [Claims] An oil separator for separating oil from a discharge gas and storing the separated oil in a discharge flow path connected to a discharge port of the compressor body, and a reserve for storing the oil-separated and cooled discharge gas. An oil-cooled screw compressor including a tank, wherein the oil separator and the reserve tank are formed below the oil separator via a partition plate in a single container. 2. The oil-cooled screw compressor according to claim 1, wherein said partition plate is formed in an arched cross section, and said arched portion is an oil reservoir. 3. The oil-cooled screw compressor according to claim 1, wherein said partition plate has an upwardly convex surface.