JP3462757B2 - Screw compressor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw compressor, and more particularly to a screw compressor suitable for efficiently separating oil in discharge gas with a simple structure.

[0002]

2. Description of the Related Art In a conventional screw compressor, an outlet of a discharge passage of a discharge casing is formed in a direction directly toward a demister arranged in a discharge chamber. Therefore, the gas discharged from the discharge casing into the discharge chamber has a flow velocity distribution and a flow rate distribution in the discharge chamber cross section, and in particular, the velocity and flow rate are large near the discharge outlet of the discharge casing and small in other parts. The passing speed and the passing flow rate of the demister were not uniform.

That is, in the portion of the entire demister near the discharge outlet of the discharge casing, the passage flow rate is large, and the passage speed greatly exceeds the optimum passage speed for oil separation of the demister, so the oil separation efficiency of the demister is remarkable. There was a problem of lowering. To solve this problem, for example, as disclosed in Japanese Patent Laid-Open No. 58-110890, a collision plate or the like is provided in the vicinity of the discharge outlet of the discharge casing to make the discharge gas in the discharge chamber have a uniform flow velocity distribution. I try to make it pass as evenly as possible over the entire surface.

[0004]

However, the above measures not only complicate the structure in the discharge chamber, but also cause problems such as damage of the collision plate and re-scattering of oil immediately after collision with the collision plate. .

In view of the above problems, it is an object of the present invention to provide a screw compressor having a simple structure, a high oil separation efficiency in discharge gas, and a small amount of oil taken out of the compressor. .

[0006]

To achieve the above object, according to an aspect of the screw compressor according to a first aspect of the present invention, at least one pair of male rotor meshed with each other, the rotor casing which dedicated female low data及 beauty bearing member, Support rotor shaft
Bearing chamber containing the bearing member for the rotor and the rotor casing
Attaching a discharge casing provided with a gas discharge path communicating with the discharge port of, while enclosing the discharge casing,
In a screw compressor having a structure in which a discharge chamber provided with a demister for oil separation is integrally attached to the rotor casing, an outlet of the discharge passage of the discharge casing is arranged in the discharge chamber. Direct the gas in the direction opposite to that of the demister and discharge gas from the outlet.
Opening for re-injecting air into the rotor casing side
I, the collision wall for colliding the inflowing gas and the oil were collided and separated
An opening II for discharging the latter gas into the discharge chamber.
The passage space is provided in the rotor casing .

To achieve the above object, a screw compressor according to a second aspect of the present invention is characterized in that, in the first aspect, an oil separating element is provided at an outlet of the discharge passage of the discharge casing. It is a thing.

[0008]

In order to achieve the above object, a screw compressor according to a third aspect of the present invention is the screw compressor according to the first or second aspect.
In the mounted screw compressor , the discharge port of the discharge chamber is provided so as to be perpendicular to the axial direction of the rotor and to be located above when installed.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a sectional structural view of a screw compressor which is an embodiment of the present invention. Prior to the present invention , FIG.
The partial detailed view of the structure of the discharge passage 29 of the discharge casing 7 in the discharge chamber 9 of the screw compressor showing the first embodiment of the invention (hereinafter referred to as "prior invention") is shown.

In the screw compressor, a motor shaft 1 is supported by a bearing 2 and a bearing 3 as shown in FIG. 1, and a suction cover 5 having a suction port 4 for introducing a suction gas from the outside is connected to each other in a sealed relationship with each other. And a discharge chamber 9 having a discharge casing 7 and a gas discharge port 8.

In the rotor casing 6, a pair of male rotors 13 supported by a suction side bearing 10 and a discharge side roller bearing 11 and a ball bearing 12 are meshed with each other, and a female rotor (not shown) is cylindrical. The shaft of the male rotor 13 is housed in the bore 14, and the shaft of the male rotor 13 is connected to the motor shaft 1 by a coupling 15 to form an intake port 16 for introducing intake gas into the cylindrical bore 14.

Further, at one end of the rotor casing 6, there is a discharge port 17 which serves as an outlet for the gas compressed by the male and female rotors.
And the roller bearing 11 and the ball bearing 12 are housed, and the roller bearing 11 and the ball bearing 1 are provided at one end of the discharge casing 7.
A shield plate 19 is provided to close the bearing chamber 18 that accommodates the two.

The discharge casing 7 is attached to the rotor casing 6 by fixing means such as bolts. The discharge casing 7 includes a cylindrical bore 14 through the discharge port 1
A gas discharge path 29 communicating with each other via 7 is formed, and a discharge port of the discharge path 29 is opened in the discharge chamber 9.

The discharge chamber 9 is provided with a demister 21 inside, and is fixed to the rotor casing 6 by a fixing means such as a bolt so as to surround the discharge casing 7. Lubricating oil 22 is stored in the bottom portion. ing. An oil supply passage is formed in the rotor casing 6 and the discharge casing 7, and is configured to connect the bottom portion of the discharge chamber 9 and each bearing portion.

Next, the flow of refrigerant gas and oil will be described. The low-temperature, low-pressure refrigerant gas sucked from the suction port 4 provided in the suction cover 5 passes through the gas passage provided between the drive motor 20 and the motor casing 23 and the air gap between the stator motor rotor, and is driven. Motor 20
After being cooled, it is sucked from a suction port 16 formed in the rotor casing 6 into a compression chamber formed by the meshing tooth surface of the male and female screw rotors and the casing.

Thereafter, the refrigerant gas is sealed in the compression chamber formed by the meshing tooth surfaces of the male and female screw rotors and the rotor casing 6 as the male rotor 13 connected to the drive motor 20 by the coupling 15 rotates. The gas is gradually compressed as the compression chamber shrinks in the axial direction, becomes high-temperature and high-pressure gas, is guided to the discharge passage 29 formed in the discharge casing 7 through the discharge port 17, and is discharged to the discharge chamber 9
Is discharged inside.

Of the compression reaction forces acting on the male and female screw rotors when the gas is compressed, the radial load is supported by the roller bearing 11 and the thrust load is supported by the ball bearing 12. The oil for lubricating and cooling these bearings is supplied from the oil reservoir provided in the high pressure portion in the rotor casing 6 through an oil passage communicating with each bearing portion by differential pressure, and is supplied in the discharge chamber 9 together with the compressed gas. Is discharged to.

As shown in FIG. 2, the oil contained in the compressed gas collides with the wall surface of the rotor casing 6 in the discharge chamber 9, and the first separation is performed. Due to the collision with the wall surface, the flow of the discharge gas is made uniform in the discharge chamber 9,
The remaining oil in the discharge gas that passes through the demister 21 is separated.

These separated oils are stored in the lower oil sump of the rotor casing 6. After the oil separation, the compressed refrigerant gas is discharged from the discharge port 8.

[0021] Figure 3 shows a second actual施例of prior invention. The oil separation element 24 is attached to the outlet of the discharge passage 29 of the discharge casing 7 by a fixing means such as a bolt to prevent the oil from collecting and scattering when passing the discharge gas.

An embodiment of the present invention is shown in FIGS. When the gas discharged from the outlet of the discharge passage 29 of the discharge casing 7 is caused to flow into the passage space 25 formed in the roller casing 6 again through the opening I26 to perform collision separation,
The oil in the gas drops by gravity and is drained from the oil drain hole 28 provided in the lower portion of the passage space 25.
Is stored in the oil sump at the bottom of the. On the other hand, cold <br/> medium gas oil has been separated is discharged into the passage space 25 provided openings II27 by Ri吐 out chamber 9.

[0023]

According to the present invention, since the outlet direction of the discharge passage of the discharge casing is formed in the direction opposite to the demister arranged in the discharge chamber, a screw compressor having a simple structure and an excellent oil separation effect is provided. it can.

Since the oil separating element is attached to the discharge passage of the discharge casing, it is possible to collect and prevent the oil from scattering when passing the discharge gas.

Further, the oil flowing from the discharge passage of the discharge casing directly into the passage space formed in the rotor casing collides with the wall of the passage space and drops, so that the oil drops again on the flow of gas and reaches the downstream side. Since the structure is such that it can be prevented from flowing out of the compressor, it is possible to obtain a screw compressor in which the amount of oil entrained outside the compressor is small.

[Brief description of drawings]

FIG. 1 is a sectional view of a screw compressor showing an embodiment of the present invention.

FIG. 2 is a partial detailed view of the discharge passage structure of the discharge casing in the discharge chamber showing the first embodiment of the prior invention.

FIG. 3 is a partial detailed view showing the second embodiment of the prior invention in which an oil separation element is provided at the outlet of the discharge passage of the discharge casing in the discharge chamber.

Partial detailed view of the discharge passage and the passage space of the rotor casing of the discharge casing in the discharge chamber showing an embodiment of the present invention; FIG.

5 is a partial detailed view of the passage space formed in the rotor casing as viewed from the direction A in FIG.

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-3-15694 (JP, A) JP-A-58-110890 (JP, A) JP-A-59-32690 (JP, A) JP-A-60- 110084 (JP, A) JP 10-159763 (JP, A) JP 60-53691 (JP, A) JP 60-47893 (JP, A) Actual development 55-25685 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) F04C 29/02 351 F04C 18/16

Claims (3)

(57) [Claims] [Claim 1] at least one pair of male rotor meshed with each other, the rotor casing which dedicated female low data及 beauty bearing member, a bearing chamber and pre paid a bearing member for supporting the rotor shaft
A discharge casing having a gas discharge passage communicating with the discharge port of the rotor casing is attached, and a discharge chamber having a demister for oil separation is integrally attached to the rotor casing while enclosing the discharge casing. in screw compressors, the outlet of the discharge path of the discharge casing, towards the opposite direction as the demister disposed in the discharge chamber
The gas discharged from the outlet again.
The opening I for flowing into the data casing side and the inflowing gas
The collision wall and the gas after the collision separation of oil
A passage space having an opening II for discharging into the discharge chamber
A screw compressor formed in the rotor casing . 2. The screw compressor according to claim 1, wherein an oil separation element is provided at an outlet of the discharge passage of the discharge casing. 3. The discharge port of the discharge chamber is connected to the row
So that it is perpendicular to the axis of the
The screw compressor according to claim 1, wherein the screw compressor is provided .