JPH0716069Y2 - Compressor - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an oil / water automatic separator applied to an air compressor, and more specifically, it is dispersed in oil which cannot be removed by a drain drainer for draining drain accumulated in the oil separator. The present invention relates to, for example, a screw compression device provided with an oil / water automatic separator capable of adsorbing even minute water.

[0002]

2. Description of the Related Art A screw compressor lubricates, seals and compresses a male rotor between a rotor and a casing in order to engage the female rotor in a casing and to confine gas in the compression space of the female rotor. Cooled oil is supplied to cool the gas. This oil is discharged together with the handling gas. Therefore, oil is separated and recovered from the compressed gas by the oil separator, cooled, and returned to the screw compressor again. When such a screw compressor is used as an air compressor, the moisture in the sucked air is compressed and condensed and separated in the oil separator, and accumulates at the bottom of the oil separator. Deteriorates the oil and reduces the lubrication and sealing performance. Therefore, this water must be drained. Since the water separated by the oil separator is a so-called drain in which oil water is mixed, an automatic oil-water separator is used to collect the oil in the drain and return it to the oil circulation circuit to drain the water.

Therefore, the present inventor has proposed the invention disclosed in Japanese Utility Model Publication No. 2-5114. The invention is a screw air compression device that includes an oil separator and returns separated oil to the screw compressor by using the discharge pressure of the screw compressor, and a drain discharger communicating with a drain discharge port of the oil separator and a drain discharger. The oil outlet of the oil filter is equipped with an oil filter equipped with an oil adsorption filter in the pipe connecting the inlet side of the oil filter connected to the oil supply pipe connecting the oil separator and the screw compressor. First, most of the water accumulated in the oil separator is discharged to the outside with a drain drainer, and fine water particles that cannot be removed by gravity separation are
Further, since the water is adsorbed by the oil filter capable of adsorbing fine water molecules, the water is better removed from the oil, so that the deterioration of the oil is not accelerated and the life of the oil is further extended. It also extends the life of screw air compressors and oil filters. Further, the filter of the oil filter itself has an advantage that the drain drainer removes most of the water by specific gravity separation in the preceding stage, so that the wear of the filter itself is small and the service life is long.

[0004]

According to the above conventional example, there is a pressure drop until it passes through the oil separator, drain drainer and oil filter, and the outlet pressure of the oil filter is lowered. Therefore, when returning oil from the oil filter to the oil supply pipe between the oil outlet of the oil separator and the oil supply port of the screw compressor, when returning the oil to the oil flow of a pressure lower than the outlet pressure of the oil filter. You cannot return the oil without returning it. Therefore, it is returned to the inlet side of the oil filter. Even if the water is returned to the inlet side of the oil filter, the water in the oil that could not be separated by the drain drainer is adsorbed by the adsorbent in the oil filter, so it passes through the water adsorbent that is the oil filter element. The resistance to the oil flow through will increase as the water adsorbs on the water adsorbent and the pressure drop across the oil filter will increase. Therefore, the oil separated by the drain drainer cannot be returned at last.

Looking at the adsorption filter in the oil filter in such a state, the water adsorbent adsorbs water and expands at the inlet side,
Although the oil passage cross-sectional area has been reduced, the water adsorbent on the downstream side adsorbs only a small amount of water, and at this point the replacement of the adsorption filter is extremely wasteful. In addition, the replacement period of the suction filter is short, and it requires manpower for the replacement.

Further, in the conventional example, the returning position of the oil returned from the oil filter is restricted. In particular, in the case of having an oil recovery circuit of a type in which the oil discharged from the oil outlet of the oil separator is pumped to the air compressor, there is a drawback that it can be returned only to the suction port side of the air compressor.

The present invention improves the above-mentioned drawbacks of the conventional compressor having an oil recovery device, makes it possible to effectively use the oil filter, and has less restriction on the returning position of the oil from the oil filter. Is intended to provide.

[0008]

According to a first aspect of the present invention, a compressed gas is used as a compression medium and communicates with a compressor that requires the supply of oil to a compression working space and a discharge port of the compressor. An oil separator that separates oil from the oil, an oil supply pipe that connects the oil outlet of the oil separator and the oil supply port of the compressor, an oil cooler and an oil filter that are interposed in the oil supply pipe, and an oil separation Equipped with a drain drainer that communicates its inlet with the drain outlet of the container, and an oil filter with a moisture adsorption filter that communicates with the oil outlet of the drain drainer that communicates with its oil outlet In the above compression device, a pump is provided between the drain discharger and the oil filter to pump the oil from the drain discharger toward the oil filter.

The second aspect of the present invention is to provide two cylindrical bores, which are parallel to each other in the casing and overlap each other such that the distance between the shafts is smaller than their diameters, respectively. A male rotor and a female rotor that are rotatably supported around and mesh with each other, and the casing has a suction side end wall and a discharge side end wall perpendicular to the bore axis at both ends of the bore, and the suction side The end wall and the discharge side end wall have an end wall suction port and an end wall discharge port, respectively, for lubrication, cooling,
A screw compressor having an oil supply port for sealing, an oil separator communicating with the discharge port of the screw compressor to separate oil from compressed gas, an oil outlet of the oil separator and an oil supply of the screw compressor. An oil supply pipe communicating with the mouth, an oil cooler and an oil filter interposed in the oil supply pipe, a drain drainage communicating the inlet to the drain discharge port of the oil separator, and an oil outlet of the drain drainer. In a screw compressor equipped with an oil filter equipped with a moisture adsorption filter, the inlet of which is in communication with the oil circulation circuit of which the outlet is in communication with the oil circulation circuit. It is a screw compression device equipped with a pump that pressure-feeds the oil toward.

[0010]

Embodiments of the present invention will be described in detail below with reference to the drawings. INDUSTRIAL APPLICABILITY The present invention is applicable to a case where a condensable substance that supplies oil in addition to a handling gas and that also has a gas phase in the handling gas or oil has a bad influence on the compression performance of a screw compressor. Since there are many problems in using a screw compressor as an air compressor, the screw type air compressor is described in the embodiment.

The screw air compressor is driven by an electric motor 8 as shown in FIG. 1, and a screw air compressor 1 sucking air from an air intake 7 and an oil separator connected to a discharge pipe 2 of the compressor 1. 3, an oil cooler 5 arranged between an oil separator 3 and an oil supply pipe 4 connecting the screw air compressor 1 and an oil filter 6 for removing dust.

The oil-water separator for separating the water accumulated at the bottom of the oil separator 3 and recovering the oil is as follows. The drain drainer 11 is connected to the bottom of the oil separator 3 via the drain drain pipe 10. The drainage means to the drain drainer 11 is a well-known means and utilizes the pressure in the oil separator 3. Although various types of drain drainers 11 are considered, one is equipped with a drain container, and when oil containing water is received in the container, the oil C is on top due to the difference in specific gravity and the water Since D becomes lower, a float switch 19 is provided which is activated only by the specific gravity of water when the water D is accumulated in a predetermined amount.

Oil outlet of drain drainer 11 and oil filter 15
A pump 20 is interposed in the circulating oil pipe 12 between the two.
The suction port of the pump 20 communicates with the drain drainer 11, and the discharge port thereof communicates with the inlet of the oil filter 15.
A normally closed solenoid valve 22 is attached to the drain pipe 21 of the drain drainer 11. In the control circuit based on the signal from the float switch 19 described above, the water level in the drain drainer 11 rises, and when the float switch 19 operates, the pump 20 is energized and stored above the upper limit water level of the drain drainer 11. The suction pipe of the pump 20 immersed in the oil sucks only the oil, pressurizes it, and discharges it. Then, when the suction of the oil is finished, the pump 20 is deenergized, the solenoid valve 22 is opened, and the float switch 19 closes the solenoid valve 22 according to the signal that the lower limit water level is detected, or closes the solenoid valve 22 with a timer. ing.

The oil filter 15 is equipped with an adsorption filter 14 capable of adsorbing fine water particles dispersed in the oil. The cylindrical adsorption filter 14 is provided in the casing 16 and the oil in the circulating oil pipe 12 is disposed. Is shown in the casing 16 and is filtered through the adsorption filter 14 from the outside to the inside.

The following examples can be given as the adsorption filter 14 described above. That is, the main component is softwood pulp,
This is a paper in which cellulose fibers having a large number of hydrophilic acid groups are formed into a thin sheet, a specific crepe is attached to the sheet, and then a slitter is formed into a roll shape, which is rich in adsorption and hydrophilicity. According to this adsorption filter 14, fine dispersed water particles of 10 micron unit in oil are physically adsorbed by the gaps between the papers. Furthermore, 1 to 0.
The ultrafine dispersed water particles of 01 micron are adsorbed by the capillary between fibers which are formed innumerably by the entanglement of the cellulose fibers.

The outlet pipe 23 of the oil filter 15 is connected to the oil supply pipe 4 at the confluence 13 on the inlet side of the oil filter 6. The confluence of the outlet pipe 23 may be the discharge pipe 2, the oil separator 3, and the oil supply pipe 4 on the inlet side of the oil cooler 5 as described later. It goes without saying that the pump 20 needs a pump having a specification of generating a pressure higher than the pressure at the confluence.

Next, the operation will be described. The air A sucked from the air intake 7 of the screw air compressor 1 is supplied to the electric motor 8
The tooth space between the pair of screw rotors that rotate with the rotor is trapped between the casing and the casing, and at the same time, the rotor is meshed and compressed. During the compression, oil is continuously injected, and the heat of compression is taken by the mist-like oil, and while substantially isothermal compression is performed, the rotor teeth and the rotor and the casing are sealed and lubricated. At the final stage of compression, the compressed air that has reached the specified pressure is discharged from the casing, and the mixed fluid B containing water and the oil and dust generated after the compression in the compressed air passes through the discharge pipe 2 and is separated into oil. Guided to vessel 3. In the oil separator 3, even the fine oil is collected by the oil separation element 9 therein, and the oil is separated and dropped, and the oil is collected downward. The compressed air A'is thereafter supplied to a device using compressed air (not shown). On the other hand, the oil C is supplied to the oil separator 3 and the screw air compressor 1 via the oil supply pipe 4.
Return to the screw air compressor 1 due to the differential pressure between them. While being cooled by the oil cooler 5 on the way, dust in the oil is removed by the oil filter 6.

In this process, the water vapor in the air becomes moisture in the mixed fluid B due to the compression of the air A in the screw air compressor 1, and this is compressed and the oil separator. In the oil separator 3, the condensed water is generated due to the temperature difference between the inside and the outside of the casing of No. 3, or the condensed water is generated at the same time when the screw air compressor 1 is stopped due to the stoppage of use of the compressed air A ′. Is water D
Accumulates.

The water contained in the oil C of the oil separator accumulates at the bottom due to the difference in specific gravity, and the drain introduced through the drain drain pipe 10 to the drain drain 11 is introduced into the drain drain 11 due to the difference in specific gravity. When it is separated into oil water and the water level rises and reaches the upper limit water level, the float switch 19 operates, the pump 20 is energized, the oil in the drain drainer 11 is sent out through the circulating oil pipe 12 and the pressure is increased, and the oil filter The water is sent to the oil filter 15, the water content in the oil is removed by the adsorbent in the oil filter 15, reaches the confluence 13 through the outlet pipe 23, and is cooled by the oil cooler 5 from the oil separator 3 and sent. The oil filter 6 removes dust and the like and is sent to the screw air compressor 1. When the oil above the upper limit water level of the drain drainer 11 is almost sucked out, the pump 20 is stopped,
The solenoid valve 22 is opened, the water accumulated in the drain drainer 11 is discharged from the drain pipe 21, and after discharge, the solenoid valve 22 is closed,
Prepare for the next oil-water separation.

In the above, the discharge pressure of the pump 20 is selected to be always higher than the pressure of the oil flowing in the oil supply pipe 4 at the confluence 13.

2 to 4 each show another embodiment.

In FIG. 2, the outlet pipe 23 of the oil filter 15 is connected to the oil supply pipe 4 on the inlet side of the oil cooler 5 at a junction 13. In this way, the oil that is temporarily supplied when the pump 20 is operating merges with the oil that has not been cooled in the oil supply pipe 4 and is cooled together, so that the oil that is supplied to the screw air compressor 1 is The temperature stabilizes.

In FIG. 3, a junction 13 is provided so that the outlet pipe 23 of the oil filter 15 flows into the oil C of the oil separator 3.

In FIG. 4, the outlet pipe 23 of the oil filter 15 is connected to the discharge pipe 2 at the confluence 13.

The embodiment is applicable to other positive displacement type compressors which require the supply of oil to the compression working space for compressing gas.

[0026]

[Effects of the Invention] Since the present invention is designed so that the oil separated by the drain drainer of the oil-water separator is pumped by a pump to an oil filter equipped with an adsorption filter, the adsorption filter in the oil filter can be used effectively. In addition, since the outlet pressure of the oil filter can be increased, there are few restrictions on the position for returning the oil that has left the oil filter, and there is a reliable return effect.

[Brief description of drawings]

FIG. 1 is a flow sheet of a first embodiment of the present invention.

FIG. 2 is a flow sheet of a second embodiment of the present invention.

FIG. 3 is a flow sheet of a third embodiment of the present invention.

FIG. 4 is a flow sheet of a fourth embodiment of the present invention.

[Explanation of symbols]

A ・ ・ Air A '・ ・ Compressed air B ・ ・ Mixed fluid C ・
・ Oil 1 ・ ・ Screw air compressor 2 ・ ・ Discharge pipe
3 ... Oil separator 4 ... Oil supply pipe 5 ... Oil cooler
6 ... Oil filter 7 ... Air intake 8 ... Electric motor 9 ... Oil separation element 10 ... Drain drainage pipe 11 ...
・ Drain drainer 12 ・ ・ Circulating oil pipe 13 ・ ・ Merging point
14 ... Adsorption filter 15 ... Oil filter 16 ... Casing 19 ... Float switch 20 ... Pump 21 ...
Drain pipe 22 ... Solenoid valve 23 ... Outlet pipe.

Claims (2)

[Scope of utility model registration request] 1. A compressor that uses gas as a compression medium and requires the supply of oil to a compression working space, an oil separator that communicates with a discharge port of the compressor, and separates oil from compressed gas, and an oil separator. An oil supply pipe that connects the oil outlet of the container and the oil supply port of the compressor,
An oil cooler and an oil filter interposed in the oil supply pipe, a drain drainer communicating its inlet with a drain outlet of an oil separator, and an oil outlet of the drain drainer with its inlet communicating with its outlet. In a compressor equipped with an oil filter connected to an oil circulation circuit and equipped with a moisture adsorption filter, a pump is provided between the drain discharger and the oil filter to pump oil from the drain discharger toward the oil filter. A compression device characterized in that 2. A cylindrical boss which is rotatably supported about the bore axis in two cylindrical bores provided in parallel with each other in the casing and overlapping each other such that the distance between the axes is smaller than its diameter. The casing has a male rotor and a female rotor that mesh with each other, and the casing has a suction side end wall and a discharge side end wall perpendicular to the bore axis at both ends of the bore, and the suction side end wall and the discharge side end wall. Each has an end wall suction port and an end wall discharge port, and is connected to a screw compressor equipped with an oil supply port for lubrication, cooling, and sealing, and communicates with the discharge port of the screw compressor to separate oil from compressed gas. Oil separator, an oil supply pipe that connects the oil outlet of the oil separator and the oil supply port of the screw compressor, an oil cooler and an oil filter interposed in the oil supply pipe, and a drain of the oil separator. Drain connecting the outlet to the outlet In a screw compressor equipped with an oil filter equipped with a water adsorption filter, the drain is connected to the oil outlet of the drain and the inlet is connected to the oil outlet, and the outlet is connected to the oil circulation circuit. A compressor equipped with a pump that pumps oil from the drain discharger toward the oil filter between the vessels.