JPH029197B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a screw compressor unit.

The screw compressor injects oil for the purpose of sealing and cooling the refrigerant gas and cooling and lubricating the rotor, bearings, and the like. In order to ensure the efficiency and improve the reliability of the compressor, oil injection can be said to be an essential and important mechanism.

However, since the oil injected into the rotor casing by this oil injection mechanism is discharged from the compressor together with the refrigerant, an oil separation process is required to separate the oil in the refrigerant gas and introduce only the refrigerant gas into the condenser. It becomes necessary. The oil separator performs this process.
This container occupies a large proportion of the entire device.

Furthermore, the connection between the compressor and the oil separator is made from the discharge casing of the compressor through the discharge piping, which requires space, assembly, and maintenance, and in the case of two or more compressors, one An oil separator is added to each compressor to form a set of compressor units.If multiple compressors are installed, such as those found in reciprocating compressors, an oil separator is added to each compressor. The disadvantage was that the device as a whole became larger due to the addition of the .

The present invention eliminates the above-mentioned drawbacks of the conventional compressor unit, and makes the compressor unit extremely compact.
It is an object of the present invention to provide a screw compressor unit which is easy to assemble and maintain, and whose structure and handling are simple especially when the number of compressors becomes complicated.

The present invention communicates the suction port 20 of the screw compressor rotor chamber with the motor internal space 19 of the motor 2 that drives the compressor screw rotor 13,
A refrigerant suction port 18 is provided in the internal space of the motor, and the compressor screw rotor 13 has a shaft end connected to a bearing 14.
A plurality of screw compressors 1, supported by a drive motor 2 on an extended shaft and integrally built into a single casing 15, are connected to the can of the oil separator 3 so that their rotor axes are vertical. It is characterized in that it is detachably attached to a flange 17 provided on the body 16, and the discharge ports 21, 21' of each screw compressor 1, 1' are opened directly into the separator chamber 22 in the oil separator 3, respectively. This is a screw compressor unit.

Embodiments of the present invention will be described using the drawings.

In FIG. 1, screw compressors 1, 1',
Two motors 2, 2' and two oil pumps 7, 7' are provided, but other main equipment is common. 8 is a strainer, 9 is an expansion valve, 10, 11, 11', 1
2 and 12' are check valves.

The screw compressors 1, 1' and the motors 2, 2' are integrally constructed as described later with reference to FIG. 2, and the refrigerant gas is sucked into the compressors 1, 1' through the internal space of the motors 2, 2'It's becoming like that.

In the evaporator 5, the refrigerant is evaporated by cooling the fluid to be cooled (eg, water, brine, air, etc.). In the embodiment shown in FIG. 1, there is one evaporator 5, but there may be a plurality of evaporators. The refrigerant gas evaporated in the evaporator 5 is branched off before the motors 2, 2' on the suction side of the screw compressors 1, 1' through the main suction pipe, and is sent to the motors 2, 2' via the check valves 11, 11'.
2' and is sucked into screw compressors 1 and 1'. The check valves 11, 11' play an important role in preventing the refrigerant gas from the screw compressor that is stopped from bypassing the screw compressor that is in operation.

In the screw compressors 1 and 1', refrigerant gas is introduced into the compression space created by the pair of screw rotors and the inner surface of the compressor casing, and
2' causes the rotor to rotate, thereby reducing the volume of the compression space and increasing the pressure.

During compression, lubricating oil is injected to cool the refrigerant gas and seal gaps between the rotor and casing. The refrigerant gas pressurized by the screw compressors 1 and 1' is discharged to the oil separator 3 together with the injected oil and some of the oil supplied to the bearings.
All discharge gases from the plurality of screw compressors 1, 1' are led to one common oil separator 3.

The oil-containing refrigerant gas from each screw compressor 1, 1' is efficiently separated from the oil at once in an oil separator 3, and is led to a condenser 4 via a check valve 10 and a connecting pipe. In the condenser 4, the refrigerant gas is cooled and condensed by cooling water or air, and is liquefied.

This refrigerant liquid passes through the liquid pipe and is depressurized and expanded by the expansion valve 9 to the evaporation pressure. The depressurized refrigerant liquid is guided to the evaporator 5 to form a refrigeration cycle. On the other hand, the oil separated in the oil separator 3 is temporarily stored at the bottom of the oil separator 3, cooled to a predetermined temperature with cooling water in the oil cooler 6, and then passed through the oil strainer 8 to each screw. It is branched to compressors 1 and 1'.

After branching, oil is supplied to the screw compressors 1, 1' for oil injection into the compression space and for bearing lubrication by the oil pumps 7, 7' which are linked to the operation of the screw compressors 1, 1'.
supplied to

FIG. 2 shows an embodiment of a screw compressor unit that combines a screw compressor and an oil separator.

The screw rotor 13 is supported by a bearing 14 that receives thrust and radial loads at the shaft end, and a drive motor 2 is built into the extension shaft of the male rotor. A plurality of hermetic compressors are attached to a flange 17 provided on a can body 16 of a horizontal oil separator 3. The suction port 18 of the screw compressor 1 opens toward the motor end side and communicates with the motor internal space 19, and the refrigerant gas evaporated in the evaporator 5 enters from the suction port 20 provided in the motor internal space 19 and enters the motor. After cooling the compressor 2, it is introduced into the compressor screw rotor 13 and compressed. The discharge port 21 of the screw compressor 1 opens directly into the oil separator 3, and the compressor screw rotor 1
The refrigerant gas discharged from the oil separator 3 is directly introduced into the oil separator 3.

The oil separator 3 is divided into two chambers, and in the first separator chamber 22 where the discharge port 21 of the compressor opens, most of the oil in the discharged gas is separated by gravity.
The refrigerant gas from which most of the oil has been separated passes through the communication port 23 and enters the second separator chamber 24 , where the remaining oil is separated by the demister 25 and discharged to the condenser 4 . The separated oil is configured to accumulate in an oil reservoir 26 at the bottom of the oil separator 3.

In particular, in this embodiment, the screw compressor 1 is a rigid hermetic compressor in which the screw rotor shaft is arranged vertically, and since the screw compressor 1 is directly assembled into the oil separator 3, it is easy to assemble. The oil supply function and bearing cooling function can be fully satisfied, and there is no need for a base or legs for the screw compressor 1.

In addition, by simply increasing or decreasing the flange of the first separator chamber of the horizontal oil separator according to the number of compressors, it is possible to
It is possible to easily install about four units from one stand. Second
The figure shows the case of two screw compressors, but even if there are many screw compressors, they can be installed compactly.
Piping can also be simplified.

The above embodiment has the following effects.

(1) Although the oil for injection is supplied between each bearing and rotor casing of the compressor separately, the oil discharged together with the discharge gas is introduced into a common oil separator, where it is separated and stored all at once. No matter what the operating condition is, there is no uneven distribution of oil and there is no problem with oil supply.

(2) Regardless of the number of compressors, the oil separator, oil cooler, and oil strainer can be configured as a single unit according to the total capacity of the compressors, which greatly simplifies the piping system and further reduces the overall cost of the equipment. Can be made smaller.

(3) Since the number of compressors can be selected arbitrarily regardless of the number of evaporators, it is possible to match the capacity precisely with a very small number of compressor types.

(4) Since the compressor rotor casing is directly attached to the oil separator, the discharge casing and discharge piping can be omitted.

(5) Assembly is easy and space for installing the compressor is not required.

According to the present invention, it is possible to provide a screw compressor unit which is extremely compact and easy to assemble and maintain, and which is particularly easy to structure and handle even when there are a plurality of compressors. be effective.

[Brief explanation of drawings]

FIG. 1 is a flow diagram of an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view of a compressor unit of the embodiment of the present invention. 1, 1'... Screw compressor, 2, 2'... Motor, 3... Oil separator, 13, 13'... Screw rotor, 14, 14'... Bearing, 15, 1
5'...Casing, 16...Can body, 17,1
7'...flange, 18,18'...suction port, 1
9, 19'... Motor internal space, 20, 20'... Suction port, 21, 21'... Discharge port, 22... First separator chamber, 23... Communication port, 24... Second separator chamber, 25...Demister, 26...Oil sump section.

Claims (1)

[Claims] 1 Screw compressor rotor chamber suction port 20;
The compressor screw rotor 13 is connected to a motor inner space 19 of the motor 2 that drives the compressor screw rotor 13, and a refrigerant suction port 18 is provided in the motor inner space, and the compressor screw rotor 13 has a shaft end supported by a bearing 14. A plurality of screw compressors 1 each having a driving motor 2 installed on an extended shaft and integrally built into a single casing 15 are installed in the can body 16 of the oil separator 3 so that their rotor axes are vertical. The screw compressor is detachably attached to a flange 17 provided in the oil separator 3, and the discharge ports 21, 21' of each screw compressor 1, 1' are directly opened into a separator chamber 22 in the oil separator 3. machine unit.