JP2583454Y2 - Air compressor - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air compressor equipped with a cleaning oil device for removing minute water contained in oil separated in an oil separator.

[0002]

2. Description of the Related Art As is well known, air compressors are used in various industries, and among them, screw air compressors are frequently used because of low noise and easy maintenance. This screw air compressor is composed of a screw compressor, an oil separator, an oil cooler and an oil filter for removing dust, and the air sucked into the screw compressor is lubricated by oil. Compressed by rotation of the screw rotor, under cooling and sealing. When the working fluid takes the atmosphere, moisture exists in the compressed air, and the oil supplied to the screw compressor mixes with the compressed air. The resulting mixed fluid of compressed air, oil, and moisture then flows into an oil separator, where it is separated into compressed air and oil, and the compressed air is supplied to equipment using compressed air and the oil is returned through a return oil pipe. Cooling again by pressure,
The dust is returned to the screw compressor while the dust is removed. In the above oil separator, a turbid drain of oil and water collects in the lower layer of the separated oil. One reason is that the screw compressor itself generates moisture in the compression process, and the other is that the use of equipment that uses compressed air has stopped and the oil separator has stopped operating when the screw compressor has stopped operating. Is generated by condensation in the oil separator, and water is accumulated in the oil separator due to condensation or the like based on a temperature difference between the inside and outside of the oil separator.

If this drain is left in the oil as it is, the oil deteriorates and the life of the oil is shortened. Also, if left as it is, the oil filter for dust removal arranged in the return oil pipe between the oil separator and the screw compressor will be severely consumed, and the oil filtration element must be replaced in a short time, and the screw compression Shorten the life of the machine.

[0004] Therefore, a technique for draining the drain in the oil separator has been conventionally used. That is, a drain drain is connected to the lower part of the oil separator, and a circulating oil pipe on the secondary side is connected to a return oil pipe between the oil separator and the screw compressor, and the drain is automatically or manually periodically discharged to the outside. The oil is drained and a small amount of oil is circulated by differential pressure. Many of such drainage devices use a difference in specific gravity of oil and water. For example, Japanese Utility Model Publication No. 59-24329 and Japanese Utility Model Publication No. 5
Such publications are disclosed in JP-A-9-12969, JP-B-59-24330, JP-B2-39529 and JP-A-56-14895.

[0005] According to these, since much of the water remaining in the oil separator is discharged to the outside, it is possible to prevent the deterioration of the oil to a considerable extent and to remove dusts between the oil separator and the screw compressor. For this purpose, the oil filter and the screw compressor itself can be prevented from being worn.

[0006]

In the oil separator, drain accumulates at the bottom due to a difference in specific gravity, and oil accumulates at the upper portion. However, fine oil particles are dispersed and mixed in this oil. A drain valve is provided at the bottom of the oil separator to drain the drain (water). Neglecting drainage will lead to oil deterioration and eventually damage to the screw air compressor. The oil is lubricated and cooled by the screw air compressor,
Has an important role such as a seal. For this reason, the person in charge of the screw air compression device must drain before starting the device. However, even if draining is completely performed before the start of the device, the oil separated by the oil separator contains many fine water droplets as already described, shortening the life of the oil and the device. I have.

Although the above description has been made with reference to the screw air compression device, the same applies to other types of oil supply type air compression devices which perform compression by sucking air.

An object of the present invention is to provide an air compressor capable of extending the life of oil and the life of an air compressor by removing minute water mixed in oil in an oil supply type air compressor.

[0009]

According to a first aspect of the present invention, oil separated from an oil separator interposed in a discharge pipe of an air compressor is compressed by an air compressor through an oil cooler and an oil filter for removing dust. In an air compressor equipped with a return oil pipe returning to the machine, a pump for pressurizing the oil and a pump for pressurizing the oil are supplied to an oil outlet pipe for providing an oil separator with a drain discharge valve and leading the oil separated from the oil separator. A clean oil provided with a return oil pipe that is provided with an oil purifier for removing water to be sent in and returns the oil purified by the oil purifier to an oil circulation circuit including the air compressor, the discharge pipe, the oil separator, and the return oil pipe. An air compression device provided with a device.

In a second aspect of the present invention, the inlet of the oil outlet pipe is connected to the return oil pipe between the oil separator and the oil cooler, and the outlet of the oil return pipe for the oil purified by the oil purifier is connected to the oil cooler. The air compressor according to the first aspect of the present invention is characterized in that a clean oil device is provided in a bypass circuit of an oil cooler, which is connected to a return oil pipe that returns oil to an air compressor at an outlet side of the oil cooler.

In a third aspect of the present invention, the inlet of the oil outlet pipe is connected to the oil separator so as to communicate with the oil layer of the oil separator, and the outlet of the return oil pipe for the oil cleaned by the oil purifier is connected to the oil outlet. The air compressor according to the first invention, which is connected to a return oil pipe that returns oil to the air compressor at an outlet side of the cooler.

In a fourth aspect of the present invention, the inlet of the oil outlet pipe is connected to the oil separator so as to communicate with the oil layer of the oil separator, and the return pipe of the oil purified by the oil purifier is connected to the oil separator. Operates the pump regardless of the stoppage of the operation of the air compressor connected to the headspace
It was made possible to be air compression apparatus according to the first invention, wherein.

[0013] The fifth invention of the present invention combines the inlet of the oil lead-out pipe to the oil separator, combined operation of the air compressor return pipe cleaned oil in oil purification device in the upper space of the oil separator Involved in stopping
The first aspect of the present invention is the air compressor according to the first invention, wherein the pump can be operated .

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

Example 1 FIG. 1 is a flow sheet of Example 1.

First, a screw air compressor to which the present invention is applied will be described.
An oil separator 3 connected to the oil compressor 3 via a discharge pipe 2, an oil cooler 5 disposed between a return oil pipe 4 connecting the oil separator 3 and the screw compressor 1, and an oil filter for removing dust. 6

The air A sucked from the air inlet 7 of the screw compressor 1 is trapped between the space between the teeth between the pair of screw rotors rotated by the motor 8 and the casing. It is compressed by shrinking. During compression, oil is continuously injected, and the heat of compression is taken away by the mist-like oil, and while substantially isothermal compression is performed, the space between the rotor teeth and between the rotor and the casing are sealed, and lubrication between the rotors and the like is reduced. Is done. The compressed air is discharged from the casing, and the mixed fluid B composed of the compressed air, the moisture generated after the compression, the oil, and dust is separated by the oil separator 3.
It is led to. Here, the compressed air A 'and the oil C
Is separated into At this time, even the fine oil is collected by the oil separating element 9, and the oil is thoroughly separated.

The compressed air A 'is supplied to a device using compressed air (not shown). On the other hand, the oil C is supplied via a return oil pipe 4 by a pressure difference between the oil separator 3 and the screw compressor 1.
Return to the screw compressor 1. While being cooled by the oil cooler 5 on the way, dust and the like in the oil are removed by the oil filter 6 for removing dust.

In this process, the compression of the air A in the screw compressor 1 causes the water vapor in the air to become moisture and to be contained in the mixed fluid B, and the temperature difference between the inside and outside of the casing of the oil separator 3. Moisture D accumulates in the oil separator 3 because condensed water is generated due to the above, or condensed water is generated at the same time when the screw compressor 1 stops when the use of the compressed air A 'is stopped.

A discharge pipe 10 is connected to the bottom of the oil separator 3. The drain discharge pipe 10 is provided with a manual or automatic drain discharge valve 11. Drain discharge valve 11
When the oil separator 3 receives the oil mixed in the water,
Oil C rises and moisture D falls due to the specific gravity difference, so when this moisture D accumulates in a predetermined amount in a predetermined amount, the float floats that operate only by the specific gravity of water detect that constant amount, A structure in which a desired electric switch is operated by the float floating operation, an electromagnetic valve or the like is opened, and moisture D is discharged to the outside is considered. Alternatively, a timer may be set for a predetermined time in which a predetermined amount of moisture D is accumulated, and the solenoid valve may be operated at a predetermined cycle to discharge condensed water to the outside. The valve may be opened to drain condensed water.

An oil separator 3 between the oil separator 3 and the oil cooler 5
From the return oil pipe 4 to which the oil inside is guided, an oil outlet pipe 12 for leading out a part of the oil in the return oil pipe 4 branches, and a pump 17 for pressurizing the led oil is interposed in the oil outlet pipe 12. And
The oil outlet pipe 12 connects the discharge port of the pump 17 and the oil purifier 15. The outlet of the oil purifier 15 is connected to the return oil pipe 4 connecting the oil cooler 5 and the oil filter 6 at a junction 13 with a clean oil return pipe 18 returning to the oil circulation circuit.

The oil purifier 15 has a cylindrical moisture adsorption filter 14 disposed in a casing 16, and the oil sent through the oil outlet pipe 12 is put into the casing 16, and the oil is passed from outside to inside of the filter 14. An example of filtering through a filter is shown.

The following example can be given as the above-mentioned moisture adsorption filter 14. That is, cellulose fiber containing softwood pulp as a main component and having a large number of hydrophilic acid groups is formed into a thin sheet, a specific crepe is applied thereto, and then a slitter is formed into a roll shape. It is a good thing. According to the moisture adsorption filter 14, fine dispersed particles of the order of 10 microns in the oil are physically adsorbed by the gap between the sheets. In addition, 1 in oil
The fine dispersed water particles of 0.01 micron are adsorbed by the capillary between countless fibers formed by entanglement of cellulose fibers and the like.

When the pressurizing pump 17 and the oil purifier 15 are provided as described above, the following operations are performed. Drain discharge valve 1
1, the drain D in the oil separator 3 is discharged before the screw compressor 1 is started. During the operation of the screw compressor 1, the water in the pressurized air is condensed in the oil separator 3 and mixed with the separated oil. This drain D is also discharged by opening the drain discharge valve 11 in a timely manner. The oil C in the oil separator 3 is returned by the pressure in the oil separator 3 and the pressure difference between the oil return position of the screw air compressor 1 and the oil in the oil pipe 4 through the oil separator 3 → the oil cooler 5 → the oil filter 6. → Proceeds to the screw compressor 1, is cooled by the oil cooler 5, and the oil filter 6 removes dust in the oil.

On the other hand, a part of the return oil is taken in from the return oil pipe 4 through the oil outlet pipe 12 by the pressurizing pump 17, pressurized and sent to the oil purifier 15. Oil purifier 15
Then, the oil enters the casing 16 and then passes through the moisture adsorption filter 14. At this time, water mixed as fine particles in the oil C is adsorbed by the water adsorption filter 14. At the same time, dust and metal powder are removed. Therefore, only the oil C reaches the return oil pipe 4 through the clean oil return pipe 18 and the junction 13 by pressurization, and flows from the oil separator 3 toward the screw compressor 1 through the return oil pipe 4. It joins, passes through the oil filter 6 for dust removal, and is returned to the screw compressor 1. In the above, the pump 17 is the oil purifier 15
Is determined such that the pressure at the outflow side of the oil purifier 15 is slightly higher than the pressure at the junction 13 of the return oil pipe 4.

In the above, continuous or intermittent operation is performed depending on the discharge amount of the pressure pump 17.

In this embodiment, the oil from which the moisture returned by the clean oil return pipe 18 has been removed returns to the space between the oil cooler 5 and the oil filter 6 and joins the oil pipe 4, so that the temperature of the oil cooled by the oil cooler 5 In consideration of the above, the amount of oil passing through the oil cooler 5 and the amount of oil passing through the oil purifier 15 are determined. In this embodiment, the pump 17 is operated only while the screw compressor 1 is operating.

Second Embodiment FIG. 2 shows a second embodiment. This embodiment is the same as the previous embodiment except that the oil introduction part of the oil outlet pipe 12 is provided directly in the tank of the oil separator 3. According to this embodiment, an appropriate position of the oil separator 3 can be selected for the oil C inlet of the oil outlet pipe 12. The performance of the moisture adsorption filter 14 of the oil purifier 15 depends on the particle size of the water in the oil. Therefore, in this embodiment, oil containing water in the oil separator 3 can be taken out in such a manner that the performance of the oil purifier 15 can be maximized.

Third Embodiment FIG. 3 shows a third embodiment. This embodiment uses a clean oil return pipe 18.
The second embodiment is the same as the second embodiment except that the return position is set to the discharge pipe 2. According to this embodiment, since the purified oil does not join to the outlet side of the oil cooler 5, the temperature of the oil supplied to the screw compressor 1 does not change depending on the amount of the oil flowing through the oil purifier 15. Further, in this embodiment, even when the screw compressor 1 is not operating, the operation of the pressurizing pump 17 is possible, and the pump 17 can be continuously operated even when the screw compressor 1 is intermittently operating. When the apparatus is operated intermittently with the compressed air tank, the discharge amount of the pump 17 may be small.

FIG. 4 shows a fourth embodiment. This embodiment is different from the second embodiment in that the return position of the clean oil return pipe 18 is set as the upper space of the oil cooler 3. According to this embodiment, similar to the third embodiment,
The pump 17 can be operated without affecting the capacity of the oil cooler 5 and regardless of the intermittent operation of the screw compressor 1. Further, in this embodiment, since the pump 17 and the oil purifier 15 can be attached to the oil separator 3 as an oil purifying device, there is no need to change the piping of the oil circulation circuit, and the oil separator and the oil purifying device are not required. Can be unitized.

[0031]

[Devised effects present invention first devised oil-in in an air compressor to derive the oil in the oil circulation circuit to remove moisture in the oil through pressurized oil purification device by the pump oil circulation circuit The effect of preventing deterioration of the oil and increasing the durability of the air compressor is provided.

[0032] Since the second invention of the present invention is provided with a pump and oil purification device as a bypass circuit for the oil cooler in the first invention, pressure of the pump because it is sufficient only pressure drop of the oil purification device, No high pressure pump is required.

The third invention of the present invention can derive the most suitable oil for moisture content state during the separation oil in the oil separator in the first invention to water removal by oil purification device. Also, the pump does not require any special pressure.

[0034] A fourth invention of the present invention is the return position of clean oil return pipe from and to the discharge pipe of the air compressor in the first invention, regardless of the operating state of the air compressor, an oil to oil purification device Since the pump for pumping can be operated, the size of the pump can be reduced. Also, it is possible to take out oil suitable for performing moisture removal in the oil purifier.

[0035] Since the fifth invention of the present invention is the location of the clean oil return pipe to the upper space of the oil separator in the first invention,
Regardless of the operation state of the air compressor, the pump for pumping oil to the oil purifier can be operated, so that the size of the pump can be reduced.
Also, it is possible to take out oil suitable for performing moisture removal in the oil purifier. Also, a clean oil device can be installed after the refueling type air compressor.
Can be easily attached.

[Brief description of the drawings]

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

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

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

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

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 screw air compressor 2 discharge pipe 3 oil separator 4 return oil pipe 5 oil cooler 6 oil filter 12 oil outlet pipe 14 moisture adsorption filter 15 oil purifier 18 clean oil return pipe

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification symbol FI F04C 29/02 341 F04C 29/02 341A (58) Field surveyed (Int. Cl. ⁶ , DB name) F04C 29/02 F04C 18 / 16 F04C 29/00

Claims (5)

(57) [Scope of request for utility model registration] An air compressor having a return oil pipe for returning oil separated from an oil separator interposed in a discharge pipe of an air compressor to an air compressor via an oil cooler and a dust removing oil filter. An oil separator is provided with a drain discharge valve, and a pump for pressurizing the oil and a water purifier for removing the water for feeding the pressurized oil are interposed in an oil outlet pipe for discharging the oil separated from the oil separator, The oil purified by the oil purifier, the above air compressor,
An air compressor, comprising: a clean oil device including a return oil pipe returning to an oil circulation circuit including a discharge pipe, an oil separator, and a return oil pipe. 2. The oil outlet pipe has an inlet connected to a return oil pipe between the oil separator and the oil cooler, and an outlet of the oil return pipe for the oil purified by the oil purifier is air compressed at an outlet side of the oil cooler. 2. The air compressor according to claim 1, wherein the air compressor is connected to a return oil pipe for returning oil to the machine, and the clean oil device is provided in a bypass circuit of the oil cooler. 3. An oil outlet pipe is connected to an oil separator so that an inlet of the oil outlet pipe communicates with an oil layer of the oil separator, and an outlet of an oil return pipe of oil purified by the oil purifier is connected to an outlet side of the oil cooler. The air compressor according to claim 1, wherein the air compressor is connected to a return oil pipe that returns oil to the air compressor. 4. An oil outlet pipe is connected to an oil separator so that an inlet of the oil outlet pipe communicates with an oil layer of the oil separator, and an outlet of an oil return pipe of oil purified by the oil purifier is connected to a discharge pipe of the air compressor. Combined air pressure
The pump can be operated regardless of the operation stop of the compressor
Air compressor according to claim 1, characterized in that the. 5. An oil discharge pipe having an inlet connected to an oil separator, a return pipe for the oil purified by the oil purifier connected to an upper space of the oil separator, and the pump being operated regardless of whether the air compressor is stopped. No luck
2. The air compressor according to claim 1, wherein the air compressor is capable of rolling .