JPH0614484U - Oil supply device in screw compressor - Google Patents

Abstract

(57) [Abstract] [Purpose] If an oil / water separator is provided in the oil supply device of a screw compressor, the pressure drop in the oil / water separator increases due to clogging in the oil / water separator.
Drain will not flow from the oil separator to the oil-water separator. Then, the oil mixed with the drain is supplied to the screw compressor. [Structure] The oil in the compressed air discharged from the screw compressor 1 is separated by an oil separator 5. The lower drain 7 in the oil tank 5a enters the oil / water separator 13 through the drain pipe 11 to be separated into oil and water, and the oil enters the screw compressor 1 from the oil supply port 3 through the circulation pipe 15 and the oil filter 9. . A galvanometer 20 was provided in the circulation pipe 15. When the flow rate at the galvanometer 20 decreases, the alarm lamp 27 lights up.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an oil supply device in which oil supplied to a screw compressor is separated by an oil separator, drain is separated from the oil, and the oil is returned to the screw compressor again.

[0002]

[Prior art]

 FIG. 3 is a flow sheet of a conventional example. The screw compressor 1 has two rotors that mesh with each other in a rotor casing. When the rotor is rotated by the motor 2, the working fluid such as the atmosphere is sucked from the suction port 4. The screw compressor 1 cools a rotor, a rotor casing, a bearing, and the like. The rotor also serves as a lubricant and a seal between the rotor casing and the tooth surfaces of the meshing portions of a pair of rotors. Oil is also supplied for the purpose of lubrication. An oil supply port 3 for this oil is provided in the rotor casing. This oil is sent to the above-mentioned refueling point through an oil passage in the rotor casing. When the discharge pressure of the screw compressor is used for lubrication, the rotor and casing lubrication points are from the low pressure section to the medium pressure section including the suction port, and all other lubrication points are the working fluid. The air is discharged from the discharge port 10 and sent to the oil separator 5. The oil separator 5 is provided with an oil separation element 5b in the upper space in the oil tank 5a, and the oil 6 is separated from the working fluid by the oil separation element 5b, and the compressed air of the working fluid is discharged from the outlet 5c of the oil separator 5. It is sent to the demand site. Oil 6 accumulates at the bottom of the oil separator 5. Moisture in compressed air is condensed in the oil tank 5a and mixed in the oil 6 in the oil 6, and due to the difference in specific gravity in the oil 6, the upper part of the oil 6 and the lower part of the oil 6 are dust and foreign matter in the working fluid. Drain 7 with the mixture of etc. is collected. The layer of oil 6 in the oil tank 5a and the oil supply port 3 of the screw compressor 1 are communicated with each other via an oil cooler 8 and an oil filter 9, and the oil 6 in the oil tank 5a is cooled by the oil cooler 8. Fine foreign matters are removed by the filter 9, and the oil is returned from the oil supply port 3 to the screw compressor 1. The drain 7 accumulated at the bottom of the oil tank 5a enters the drain pipe 11 having an inlet opening at the bottom of the oil tank 5a, and through the drain valve 12 through the inlet passage 13b in the lid 13a of the oil / water separator 13 and the lid. Through the coalescer filter element 14 provided in 13a, it enters the container 13c with the lid 13a. The coalescer (trade name) filter element 14 has a function of condensing the water in the oil, and the condensed water is collected at the bottom of the container 13c. The oil 6 is guided to the oil filter 9 by the circulation pipe 15 through the outlet passage 13d of the lid 13a, merges with the cooled oil 6 discharged from the oil cooler 8 to lower the temperature, is filtered, and is supplied from the oil supply port 3. It is supplied to the screw compressor 1. On the other hand, the drain is discharged from the bottom of the container 13c of the oil / water separator 13 by the automatic drain discharger 16. In some cases, the oil separated by the oil / water separator 13 is directly returned to the screw compressor 1.

[0003]

[Problems to be solved by the device]

 Since the coalescer filter element is an ultra-fine fiber membrane, it is hard to see when it is durable, and the drain flow rate gradually decreases after long-term use. When the drain flow in the oil / water separator 13 becomes small, the drain 7 increases at the bottom of the oil tank 5a of the oil separator 5 so that the oil containing the drain 7 flows to the oil cooler 8 and the oil filter 9 Even if it is filtered with, the oil with moisture is supplied to the screw compressor, which reduces the lubrication and sealing performance of the screw compressor and reduces the compression capacity.

In order to prevent this, a so-called oil signal for visually observing the flow of fluid is provided in the drain pipe 11. However, since the dark-colored drain flows, the absolute flow rate is small and the oil signal It is difficult to determine whether or not it is flowing, and it is a troublesome task. For this reason, maintenance personnel tend to think that the coalescer filter element is durable, and therefore supplies poor oil to the screw compressor especially when it becomes clogged early. It is easy to overlook this. As a result, the life of the screw compressor is shortened, resulting in a large economic loss.

Therefore, there is a method of providing a pressure gauge A at the inlet of the oil-water separator and providing a pressure gauge B at the outlet to check the differential pressure of the pressure, but the pressure PA indicated by the pressure gauge A is almost the discharge pressure P of the working fluid. The pressure PA 'of the pressure gauge A'at the oil cooler inlet is almost the discharge pressure P, and the pressure PB' of the pressure gauge B'at the outlet of the oil cooler 8 is the intermediate pressure in the working space of the screw compressor 1. When it is determined that the pressure oil can be sent to the pressure gauge PB ', the pressure gauge PB' shows a considerably large pressure. Therefore, the range in which the increase amount of the pressure drop in the coalescer filter element 14 can be measured by the pressure gauges A and B is limited to an extremely small range.

[0006] The present invention is capable of reliably knowing a decrease in the capacity of an oil-water separator of a screw compressor equipped with an oil separator, an oil-water separator, and thereby maintaining the durability of the screw compressor. The purpose is to provide an oil supply device.

[0007]

[Means for Solving the Problems]

 A first aspect of the present invention is to provide an oil separation circulation circuit in which a discharge port of a screw compressor, an oil separator, an oil cooler, an oil filter, and an oil supply port of a screw compressor are connected in this order, and further an oil separator, In the oil supply device of the screw compressor in which the oil-water separator and the oil filter are provided in this order, a galvanometer was installed between the oil-water separator and the oil filter, which outputs a signal when the oil flow rate falls below a certain level. This is an oil supply device for a screw compressor.

A second aspect of the present invention is to provide an oil separation circulation circuit in which a discharge port of a clew compressor, an oil separator, an oil cooler, an oil filter, and an oil supply port of a screw compressor are connected in this order, and further. In the oil supply device of a screw compressor that has an oil-water separator, an oil-water separator, and an oil-water separation circuit in this order, a signal is emitted when the oil flow rate between the oil-water separator and the screw compressor falls below a certain level. This is an oil supply device in a screw compressor, which is provided with a galvanometer.

[0009]

【Example】

 Embodiments of the present invention will be described below. FIG. 1 is a flow chart of an embodiment of the present invention.

An oil separation circulation circuit is provided in which the discharge port 10 of the screw compressor 1, the oil separator 5, the oil cooler 8, the oil filter 9, and the oil supply port 3 of the screw compressor 1 are connected in this order. Since the oil / water separation circuit is provided in the order of the separator 5, the oil / water separator 13, and the oil filter 9, the detailed description thereof will be omitted.

According to the present invention, in the above, a galvanometer 20 is provided between the oil / water separator 13 and the oil filter 9 to emit a signal when the flow rate of the oil falls below a certain level. That is, the galvanometer 20 is provided in the circulation pipe 15.

FIG. 2 is a vertical sectional view of the galvanometer 20. The galvanometer 20 accommodates the body 18 in which the O-rings 19 are fitted in the recesses at both ends between the rectangular box-shaped frame 17 having no bottom, and the inlet pipe joint 21 and the outlet pipe joint 22 are provided on the opposing walls of the frame 17. The body 18 is screwed and pressed by the joints 21 and 22 through the O-ring 19 to seal the space between the inlet pipe joint 21, the outlet pipe joint 22 and the body 18 and hold the body 18 against the frame 17. . The body 18 is provided with a cylindrical hole 18a in which the magnet-containing float 23 is loosely fitted on the inlet pipe joint 21 side, and the cylindrical hole 18a is followed by the cylindrical hole 18a toward the outlet pipe joint 22 side. Is also provided with a large diameter cylindrical hole 18b. A compression coil spring 24 is contracted between the magnet-containing float 23 and the inlet pipe joint 21 in the expanded cylindrical hole 18b, whereby the magnet-containing float 23 is in contact with the inlet pipe joint 21. The magnet-containing float 23 has a hollow cylindrical shape with an end plate on the side of the compression coil spring 24 that serves as a spring seat, and a valve port 23a on the side. The valve port 23a is closed by the cylindrical hole 18a of the body 18 in the state shown in the figure, and when it moves to the right in the figure, it opens in the enlarged diameter cylindrical hole 18b as desired. A reed switch 25 is attached to the concave portion on the outer periphery of the body 18. The reed switch 25 is disposed at a position where the magnet-containing float 23 is operated when the magnet-containing float 23 made of a material in which magnetic powder is mixed in aluminum is moved. Lead wires 25a and 25b are led out to the reed switch 25, and both of them are wired to a power source 26 as shown in FIG. 1. An alarm lamp 27 is provided on the wiring connected to one lead wire 25a. ing.

In this embodiment, a strainer 28 having a coarser mesh than the coalescer filter element 14 is provided on the drain pipe 11 on the inlet side of the oil / water separator 13.

When the motor 2 is energized to continue the operation of the screw compressor 1, a drain 7 collects at the bottom of the oil tank 5a, and the separated oil 6 forms a layer on the drain 6, which is the oil cooler. It is cooled by 8 and debris is removed by an oil filter 9, and is supplied from the oil supply port 3 to the screw compressor 1. This drain 7 is passed through a manual or automatic drain valve 12, a coarse foreign substance is removed by a strainer 28, enters an oil / water separator 13 through an inlet passage 13b, and enters or exits the coalescer filter element 14. By the action of the core arrester filter element 14, the drainage is agglomerated and the grains are enlarged to accumulate at the bottom of the container 13c, and the oil in the drain 7 passes through the outlet passage 13d and enters the detector 20.

The pressure of the oil at the outlet of the oil / water separator 13 is slightly lower than the discharge pressure of the screw compressor 1, but much higher than that at the inlet side of the oil filter 9. Therefore, in the galvanometer 20, in FIG. 2, the magnet-containing float 23 is located at the rightward position by compressing the compression coil spring 24, and the valve port 23a is opened to the enlarged diameter cylindrical hole 18b. Goes through the inlet pipe joint 21, the valve port 23a of the magnet-containing float 23, the expanded cylindrical hole 18b, and the outlet pipe joint 22 into the circulation pipe 15, and the oil cooled by the oil cooler 8 at the inlet side of the oil filter 9 Join up with. At such a position that the magnet-containing float 23 moves to the outlet pipe joint 22 side, the reed switch 25 is in an open state, and the circuit from the power supply 26 is cut off, so the alarm lamp 27 is turned off. . With long-term use, the coalescer filter element 14 gradually becomes smaller and the pressure drop in the coalescer filter element 14 increases, the flow rate of the drainage passing through the coalescer filter element 14 decreases, and the drainage is separated. The flow rate of oil passing through the inlet passage 15d and passing through the galvanometer 20 is also reduced. When the flow rate and pressure of the oil at the inlet of the galvanometer 20 are reduced, the magnet-containing float 23 is retracted by the spring force of the compression coil spring 24, and the opening of the valve opening 23a of the float 23 is reduced. When the flow rate and the pressure further decrease, the magnet-containing float 23 is pushed to the inlet pipe joint 21 by the spring force of the compression coil spring 24, whereby the reed switch 25 is closed and the alarm lamp 27 is turned on. . In this state, a slight amount of oil may leak through the gap between the magnet-containing float 23 and the cylindrical hole 18a of the body 18.

In the embodiment, the oil is circulated by the discharge pressure of the screw compressor. However, in addition to the discharge pressure, the pump is pressurized and then the oil is forcedly supplied from the oil supply port 3 to the screw compressor. Is also the same.

In the embodiment, the oil separated by the oil / water separator is returned to the inlet side of the oil filter, but the present invention is also applicable to the one in which the oil is directly returned to the screw compressor.

[0018]

[Effect of device]

 The present invention provides an oil separation circulation circuit in which a discharge port of a screw compressor, an oil separator, an oil cooler, an oil filter, and an oil supply port of a screw compressor are connected in this order, and further an oil separator, an oil water separator, In the oil supply device of the screw compressor that has the oil-water separation circuit in the order of the oil filter or the screw compressor, install a detector between the oil-water separator and the oil filter that outputs a signal when the oil flow rate is below a certain level. Since it is an oil supply device for a screw compressor characterized by being provided, it is overlooked that the drain is not discharged due to the filter element in the oil / water separator, which shortens the life of the screw compressor. It is effective in preventing the case of becoming.

[Brief description of drawings]

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

FIG. 2 is a vertical sectional view of a galvanometer.

FIG. 3 is a flow sheet of a conventional example.

[Explanation of symbols]

 1 Screw Compressor 3 Oil Supply Port 5 Oil Separator 6 Oil 7 Drain 8 Oil Cooler 9 Oil Filter 13 Oil Water Separator 20 Galvanometer 23 Magnet Float 24 Compressed Coil Spring 25 Reed Switch 27 Alarm Lamp

Claims (2)

[Scope of utility model registration request] 1. A discharge port of a screw compressor, an oil separator,
An oil separation circulation circuit that is connected in the order of the oil cooler, the oil filter, and the oil supply port of the screw compressor is provided, and an oil water separation circuit is further provided in the order of the oil separator, the oil water separator, and the oil filter. An oil supply device for a screw compressor, characterized in that, in the oil supply device, a galvanometer that emits a signal is provided between an oil-water separator and an oil filter when the flow rate of oil falls below a certain level. 2. A discharge port of a screw compressor, an oil separator,
A screw compressor in which an oil cooler, an oil filter, and an oil separation circulation circuit that is connected in the order of the oil supply port of the screw compressor are provided, and then an oil separator, an oil water separator, and an oil water separator circuit are provided in this order. In the oil supply device of
An oil supply device for a screw compressor, comprising a galvanic device provided between the oil-water separator and the screw compressor to emit a signal when the flow rate of the oil falls below a certain level.