JPH07158582A - Oil free scroll compressor - Google Patents

Abstract

PURPOSE:To provide a compressor which is constituted to execute high-efficient cooling of the outer surface of the fixed scroll of an oil free scroll compressor, suppress the temperature of discharge air of the compressor to a value lower than a specified temperature, and provide high reliability and high performance. CONSTITUTION:A fin cooling duct 11 and a cooler cooling duct 10 are arranged for respective heat loads of the fixed scroll cooling fin 2 and the after cooler 4 of an oil free scroll compressor 1. A duct is sucked by a single cooling fan 12 and outside air is introduced directly to the cooling fin 2 and the after cooler 4. This constitution improves the heat efficiency of the fixed scroll and the after cooler 4, performs selection of size optimum to fan capacity, and provides the high reliability and high performance oil free scroll compressor 1 through the decrease of the discharge temperature of the oil free scroll compressor 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in oil-free scroll compressors used in air compressors and the like.

[0002]

2. Description of the Related Art Conventionally, as disclosed in, for example, Japanese Patent No. 1774245, a cooling method for an oil-free scroll compressor has been disclosed. In the system of the cooling method, the aftercooler, the cooling fan of the scroll compressor, etc. are provided independently of each other, and the drive motors are connected to each, so the compressor is not sufficiently cooled, and the drive motors, etc. However, there are drawbacks such as a large number of required devices and an increase in the size of the entire system.

[0003]

Since the oil-free scroll compressor does not have a cooling medium in the compression chamber, the discharge air temperature becomes as high as about 150 to 200 ° C. due to the heat of compression. Therefore, it is very important to commercialize an oil-free scroll compressor by mounting fins on the surface of the fixed scroll and cooling it from the outside.

An object of the present invention is to provide an oil-free scroll compressor which efficiently cools the oil-free scroll compressor, has a low discharge temperature, and has high performance and high reliability.

[0005]

In order to achieve the above object, the present invention provides a cooling fin on the outer surface of a fixed scroll of an oil-free scroll compressor, a fan for cooling the cooling fin, and an aftercooler of the compressor. A fan for cooling is shared to reduce the power of the cooling fan and improve the cooling efficiency. The fan duct on the cooling side of the aftercooler and the cooling duct on the fixed scroll cooling side of the scroll compressor are separately provided, and a fan suction structure of a type in which these are assembled is provided.

[0006]

With respect to one cooling fan, two heat loads of the aftercooler and the fixed scroll of the oil-free scroll compressor are arranged on the intake side of the cooling fan. It is arranged so that cool air can be introduced, and the cool air of the outside air is directly sucked into the heat load to perform efficient cooling.

By separately driving the cooling fan from the motor for driving the oil-free scroll compressor, the cooling fan load can be selected independently of the load on the compressor side, and the fan capacity can be freely selected. The cooling fan can be made larger, and the scroll compressor can be cooled sufficiently.

Since the oil-free scroll compressor supplies oil-free air, a cooling medium such as oil cannot be put into the compressor, and there is no cooling medium in the compression process.
If the fixed scroll is not sufficiently cooled externally, the discharge air temperature rises above about 200 ℃, and the revolving scroll and the fixed scroll are deformed due to thermal deformation. The performance of the compressor is significantly reduced due to the air leakage, but the cooling is also important in this respect. As for the aftercooler, the temperature of the discharge air discharged from the compressor is cooled from about 150 to 200 ° C to about 55 ° C and supplied to the discharge line.

[0009]

FIG. 1 shows a flow sheet of an embodiment of the present invention.
The embodiments of the present invention will be described below.

In FIG. 1, reference numeral 1 denotes an oil-free scroll compressor (the shape of the scroll inside the compressor is not shown), and a fixed scroll cooling fin 2 is provided in the compressor.
Is provided. Although the direction of the cooling fins is schematically shown in the figure as being orthogonal to the direction of the flow of the cooling air, it is actually the same as the direction of the flow of the cooling air. The discharge part of the compressor is pipe-connected to the aftercooler 4 via the check valve 3, and the suction part is pipe-connected to the suction filter 5. The scroll compressor 1 is driven by a motor 6 arranged outside the scroll compressor 1 via a transmission means such as a V-belt 7. The operation management of the oil-free scroll compressor is performed by the control panel 8 and the instrument panel 9.
The air discharge portion of the cooler cooling duct 10 for sucking air from the aftercooler 4 and the compressor cooling duct 11 for sucking air from the oil-free scroll compressor is provided in the cooling fan 12 driven by the motor 16. It is connected to the suction unit.

In the soundproof cover or casing 20 for accommodating the above-mentioned main components, an intake port 13 for taking air into the casing is formed by a filter and a labyrinth path, and an exhaust port 14 is provided on the outlet side of the cooling fan 12. Has been formed.

One embodiment of the present invention is configured as described above. Explaining the flow of compressed air in the oil-free scroll compressor, the outside air sucked from the suction filter 5 is the oil-free scroll compressor. Compressed by 1. High temperature compressed (about 150-200 ° C),
High-pressure (about 4 to 9 kg / cm ² ) air is fed into the aftercooler 4 via the check valve 3. The compressed air sent to the aftercooler 4 is heat-exchanged by the aftercooler, cooled to about 55 ° C., sent under pressure from the discharge port 15 to the air piping line, and used as high-pressure air in the demand section. The cooling air that exchanges heat with the compressed air in the aftercooler 4 is taken in through the intake port 13 and becomes high temperature due to the heat exchange with the compressed air in the aftercooler,
It is sucked by the cooling fan 12 through the cooling duct 10 and discharged from the exhaust port 14.

The fixed scroll cooling fins 2 of the oil-free scroll compressor 1 are cooled on the suction side of the cooling fan 12 via the compressor cooling duct 11 and the cooling air of the outside air from the intake port 13 is fixed scroll cooling fins. It is carried out by flowing between the two and exchanging heat with the heat load inside the compressor.

On the other hand, in the heat exchange of the high-temperature compressed air flowing in the aftercooler 4, cooling air is caused to flow into the aftercooler 4 by the cooling fan through the cooler cooling duct 10.
Cool the compressed air in the cooler.

As described above, according to the embodiment of the present invention, the fixed scroll cooling fins 2 and the aftercooler 4 of the oil-free scroll compressor 1 are efficiently used by the same cooling fan and the fan motor 16 separately installed from the drive system. It is possible to cool the compressed air in the compressor and the aftercooler by providing an independent cooling fan duct for each heat load.

In the above embodiment, one after-cooler and one scroll compressor have been described, but more cooling fans may be added and the cooling fan may be driven by one fan motor. Of course.

[0017]

The effects of the present invention are as described below.

(1) Since a plurality of cooling ducts are provided for two or more heat loads and the outside air can be directly introduced to each heat load, each heat load of the fixed scroll cooling fins, the aftercooler, etc. can be efficiently used. Can be cooled well.

(2) An optimal cooler capacity for each heat load can be selected by disposing the compressor drive motor and the cooling fan motor separately.

(3) Since the outside air can be directly introduced to each heat load, the cooler can be downsized.

(4) The cooling fan motors can be unified and integrated, and the structure can be simplified.

(5) The oil-free scroll compressor can be sufficiently cooled, and the discharge air temperature is about 200.degree.
The following can be achieved, scrolls can be prevented, and the gap between scrolls can be optimized, which improves the efficiency of the compressor and enables commercialization.

[Brief description of drawings]

FIG. 1 is a diagram showing a flow sheet of an embodiment of an oil-free scroll compressor of the present invention.

[Explanation of symbols]

1 ... Oil-free scroll compressor, 2 ... Fixed scroll cooling fins, 3 ... Check valve, 4 ... Aftercooler, 5 ...
Suction filter, 6 ... Motor, 7 ... V belt, 8 ...
Starter panel, 9 ... Instrument panel, 10 ... Cooler cooling duct, 11 ...
Compressor cooling duct, 12 ... Cooling fan, 13 ... Intake port,
14 ... Exhaust port, 15 ... Discharge port, 16 ... Cooling fan motor

Claims (1)

[Claims] 1. An oil-free scroll compressor has fins for cooling a fixed scroll of the oil-free scroll, and a cooling duct for cooling the fins and a cooler duct for cooling the aftercooler are independently arranged. In addition, a cooler duct assembly is provided upstream of this, and the cooling fan has a structure that sucks it in, and the fins of the fixed scroll and the aftercooler can directly introduce outside air. Characteristic oil-free compressor.