JPH04103887A - Oil tank in oil-cooling type compressor - Google Patents

Abstract

PURPOSE:To stabilize the operation of a detecting device during the operation by detecting the oil level depending on a lubricant put in a connecting chamber communicating its one end to a compressed air side and the other end to a lubricant side. CONSTITUTION:A bypass 13 for detection whose one end is communicated to the air side separated an adequate distance Ha from the oil level in an oil tank 2, and the other side end communicated to the lubricant 11 side separated an adequate distance Ho from the oil level is formed. And an oil level detector 12 is installed to a specific position of the bypass pipe 13. As a result, since the oil level can be detected by the lubricant flowing in from the other side end of the bypass pipe 13, the variation of the electrostatic capacity of the oil level detector 12 by receiving an influence of the lubricant being stirred can be prevented even though the lubricant 11 is stirred up in the oil tank 2 during the operation. Consequently, the operation of the detecting device can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in the structure of an oil tank in an oil-cooled compressor provided with a detection device for detecting the oil level position.

[Conventional technology] FIG. 4 shows an example of the configuration of a conventional oil-cooled compressor.

In this oil-cooled compressor, a compressor 1 takes in air and compresses it, and during the compression process, the air is passed through an oil cooler 4.
By being cooled by lubricating oil supplied from
The air is compressed to a desired rated pressure, and the air compressed to the desired pressure is sent to the oil tank 2 together with oil. Inside the oil tank 2, the oil sent from the compressor 1 becomes a mist and accumulates at the bottom, while air separates from the oil and moves upwards, where the oil is removed by the element 3 located at the upper position.
The air is discharged from the discharge pipe 10 as clean air. The clean air passing through the discharge pipe 10 passes through the pressure regulating valve 6 and the aftercooler 5, where it is cooled and discharged.

The oil removed by the element 3 passes through the recovery pipe 9 and is recovered to the suction side of the compressor 1, and the lubricating oil accumulated in the lower part of the oil tank 2 increases the pressure inside the oil tank 2 and the compressor 1. Due to the pressure difference with the oil supply section, the oil passes through the oil cooler 4, is cooled by the oil cooler 4, and is supplied to the compressor 1.

In addition, the oil tank 2 is provided with an oil level gauge 8 for checking whether the lubricating oil is contained in the amount necessary for operation, and a capacitance type oil level detector 12 is attached. When the lubricating oil 11 falls below a controlled oil level, which is a specified amount, an oil level detector 12 detects this and displays a message to that effect.

[Problem to be solved by the invention] By the way, the oil tank 2 in the oil-cooled compressor shown above
However, no consideration is given to the fact that the oil level detector 12 is adversely affected during operation and stoppage of the apparatus.

That is, when lubricating oil is sent together with air by the compressor 1 during operation, the lubricating oil causes the oil 1 in the oil tank 2 to
1 will be stirred up, the capacitance of the oil level detector 12 will fluctuate, causing the problem that the operation of the oil level detector 12 will become unstable.

Further, when the engine is stopped, it is necessary to open the air release valve 7 to release the compressed air in the oil tank 2 to the atmosphere, but at this time, a phenomenon occurs in which the oil 11 bubbles in the oil tank 2. Therefore, when the oil 11 bubbles in the oil tank 2, the oil 11 and air become mixed, so the capacitance of the oil level detector 12 changes, and the oil level before stopping changes to the oil level detector 12. Even if it exceeds the limit, the oil level detector 12 will be in a state where it appears to be in the air, causing a problem of malfunction.

In view of the problems of the prior art described above, an object of the present invention is to provide an oil-cooled compressor that can stabilize the operation of the detection device during operation and reliably prevent the detection device from malfunctioning when stopped. Our objective is to provide oil tanks for

[Means to solve the problem] In order to achieve the above object, one aspect of the present invention is as follows.

forming a detection communication chamber with one end communicating with the air side separated by an appropriate distance from the oil level in the oil tank, and the other end communicating with the lubricating oil side separated by an appropriate distance from the oil level;
It is characterized in that the oil level detector is attached to a predetermined position of the detection communication chamber.

[Effect] When the equipment is operating, lubricating oil is discharged together with compressed air in the oil tank, so the lubricating oil is stirred up in the oil tank, which causes the capacitance of the oil level detector to fluctuate. There is a risk.

However, as mentioned above, one end of the detection communication chamber communicates with the air side at an appropriate distance from the oil level in the oil tank, and the other end communicates with the lubricating oil side at an appropriate distance from the oil level. Since the lubricating oil flowing from the other end of the detection communication chamber can be used to perform the oil level horizontal ratio, even if the lubricating oil is stirred in the oil tank, the influence of the stirred lubricating oil is not affected It is possible to prevent the capacitance from changing and to appropriately detect the oil level.

Furthermore, when the compressed air inside the oil tank is released by opening the air release valve when the engine is stopped, the inside of the oil tank bubbles as the compressed air expands.

However, since one end of the detection communication chamber is connected to the air side at an upper position with respect to the oil tank at an appropriate distance, bubbles generated at an upper position in the oil tank pass through the detection communication chamber. Since the other end of the detection communication chamber is connected to the lubricating oil side at an appropriate distance, bubbles generated in the lubricating oil enter the detection communication chamber through the other end. Never. Therefore, since no bubbles enter the detection communication chamber, the capacitance of the oil level detector does not change, and malfunction of the oil level detector can be reliably prevented.

[Example] An example of the present invention will be described below with reference to FIGS. 1 to 3.

In Fig. 1, a compressor 1 sucks in air and compresses it, and during the compression process, the air is cooled by lubricating oil supplied from an oil cooler 4, and is compressed to a desired rated pressure. is sent to the oil tank 2 together with oil.

Inside the oil tank 2, the oil sent from the compressor 1 becomes a mist and accumulates at the bottom, while air separates from the oil and moves upwards, and is separated by the oil separation element 3 located at the upper position. The oil is removed and the air is discharged from the discharge pipe 10 as clean air.

The clean air passing through the discharge pipe 10 passes through the pressure regulating valve 6 and the aftercooler 5, where it is cooled and discharged.

The oil removed by the element 3 passes through the recovery pipe 9 and is recovered to the suction side of the compressor 1, while the lubricating oil 11 accumulated at the bottom of the oil tank 2 increases the pressure inside the oil tank 2 and the compressor. Oil cooler 4 due to the pressure difference with oil supply part 1
The oil is cooled by the oil cooler 4 and supplied to the compressor 1.

Furthermore, since the air that has passed through the element 3 still contains minute amounts of oil, the oil level in the oil tank 2 will drop if the device is operated for a long time. Therefore, the oil tank 2 is provided with an oil level gauge 8 for checking whether the lubricating oil is contained in the amount necessary for operation, and a capacitance type oil level detector 12 is attached to the oil tank 2. When the lubricating oil 11 falls below a specified level of control oil level, an oil level detector 12 detects this and displays a display on a display panel (not shown) indicating that the oil level has dropped.

In this embodiment, the oil level detector 12 is attached to a bypass pipe 13 formed in the oil tank 2 and serving as a communication chamber for detection. That is, the bypass pipe 13 is
It is installed at a side position of the oil tank 2, and its upper end 13a communicates with the air at a position above the oil level in the oil tank 2 at a distance Ha, and its lower end 13b communicates with the air at a position above the oil level in the oil tank 2. Lubricating oil 11 at a lower position separated by a distance Ho from the surface position
I am in touch with you. Of these distances 11Ha and HO.

The distance Jli Ha is the dimension to the air part that is not affected by the foaming even if foaming occurs due to removing the compressed air in the oil tank 2 when the equipment is stopped, and the distance @ Ho is the dimension to the air portion that will not be affected by the foaming. This is the dimension up to the lubricating oil that is not affected by the

Incidentally, in the oil tank 2, the limit distance Hb from the oil surface position to the oil side affected by bubbling, and the limit distance Hu from the oil surface position to the air side affected by bubbling can be expressed by the following equations.

Hb(rm)=(RXQoXt)÷((7C/4)D2
)X (P2/P engineering)×10 Hu (mm) = (RxQoxt) ÷ ((π/4)D”
) IO R: Ratio between foam growth rate (07 seconds) and oil tank oil amount (12) (bubble growth rate/oil tank oil amount) Qo: Oil tank oil amount (Q) D: Oil tank diameter (] ) Pi: Oil tank pressure before air release (kgf/af abs
) P2: Oil tank pressure after air release (kgf/af ab
s) t: Air release time (seconds) N: Specific heat ratio Therefore, each of the paths 1iHa and Ho has a dimension larger than the critical distance Hu on the air side and the critical distance Hb on the oil side, and both of them are affected by foaming. is set up to ensure that no one will be affected.

Then, with the distances Ha and Ho mentioned above, the upper end portion 13a,
Bypass pipe 13 whose lower end 13b is connected to the oil tank 2
Oil level detected at a predetermined position! 12 is installed.

Since the embodiment has the configuration as described above, its operation will be described next.

When the device is operating, lubricating oil 1 is released together with compressed air in oil tank 2.
1 is discharged, the lubricating oil 11 will be stirred within the oil tank 2, which may cause the capacitance of the oil level detector 12 to fluctuate.

However, as mentioned above, the oil level detector 12 is attached to the bypass pipe 13 installed on the side of the oil tank 2.
Lubricating oil 1 flowing from the lower end 13b side of the bypass pipe 13
Since the oil level can be detected by 1, even if the lubricating oil 11 is stirred in the oil tank 2, it will not be affected by the stirred lubricating oil 11, and the capacitance will not fluctuate. By being able to prevent this and properly detect the oil level, the operation of the oil level detector 12 can be stabilized.

Furthermore, when the compressed air inside the oil tank 2 is released by opening the air release valve 7 when the engine is stopped, the inside of the oil tank 2 bubbles due to the expansion of the compressed air. At this time, when the bubbles rise from the oil level position before stopping, they extend up to a limit distance Hu, and when going downward from the oil level position before stopping, they extend up to a limit distance Hb.

However, since the upper end 13a of the bypass pipe 13 is connected to the air side of the oil tank 2 at an upper position with a distance Ha larger than the limit distance Hu, bubbles generated at the upper position pass through the upper end 13a. does not enter the bypass pipe 13, and since the lower end 13b of the bypass pipe 13 is connected to the lubricating oil side at the lower position with a distance Ho greater than the limit distance Hb, bubbles generated in the lubricating oil 1 are absorbed into the lower end of the bypass pipe 13. It does not enter the bypass pipe 13 through 13b.

Therefore, since no bubbles enter the bypass pipe 13, the capacitance of the oil level detector 12 does not change significantly, and malfunction of the oil level detector 12 can be reliably prevented.

FIGS. 2 and 3 show other examples of the present invention, respectively.

First, in the embodiment shown in FIGS. 2(a) and 2(b).

A curved partition plate 15 is attached to one side of the oil tank 2, and a partition chamber 16 as a detection communication chamber is defined by the partition plate 15 and a part of the outer peripheral wall forming the oil tank 2. There is. The upper part 16a of this partition chamber 16 extends a distance H above from the oil level position as in the embodiment shown in FIG.
The lower part 16b is connected to the lubricating oil 11 side at a distance HO from the oil level position, and the oil level detector 12 is attached at a predetermined position. ing.

In the embodiment shown in FIG. 3, a cylindrical partition plate 17 is formed in the center of the oil tank 2.
A partition room 18 is defined by. The upper part 18a and lower part 18b of the partition chamber 18 also have distances Ha and Ha, similar to the embodiments shown in FIGS. 1 and 2, and the oil level detector 12 is installed at a predetermined position thereof.

According to the embodiment shown in FIGS. 2 and 3, the partition chambers 16 and 18 as detection communication chambers are formed in the oil tank 2, so even if the lubricating oil 11 is stirred during operation, Further, even if bubbles are generated during the stoppage, the stirred lubricating oil 11 and bubbles can be partitioned off by the partition chambers 16 and 18, and the same effects as in the first embodiment can be obtained.

In each of the embodiments, the oil tank 2 has a vertical structure, but the present invention is not necessarily limited to this type, and can also be applied to, for example, an oil tank with a horizontal structure. Of course, it is possible to do so.

[Effects of the Invention] As described above, according to claim 1 of the present invention, one end communicates with the compressed air side separated by an appropriate distance from the oil level in the oil tank, and the other end communicates with the compressed air side separated from the oil level by an appropriate distance. A detection communication chamber is formed that communicates with the lubricating oil side separated by an appropriate distance, and the oil level detector detects the oil level based on the lubricant that has entered the detection communication chamber, so the oil level is detected during operation. Even if the lubricating oil in the tank is stirred, the stirred lubricating oil will not affect the detection communication chamber, stabilizing the operation of the oil level detector, and preventing bubbles from forming when the tank is stopped. Even if it occurs,
As a result of being able to reliably prevent the oil level detector from malfunctioning, there is an effect of increasing the reliability of the oil tank.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an oil-fed compressor showing a first embodiment of the present invention, and FIGS. 2(a), (b), and 3 are main parts showing other examples of oil tanks. An explanatory cross-sectional view, an explanatory longitudinal cross-sectional view, an explanatory longitudinal cross-sectional view, and FIG. 4 are explanatory views showing an example of the configuration of a conventional oil-fed compressor. 2...Oil tank, 12...Oil level detector, 13...
Bypass pipe as a detection communication chamber, 13a... upper end of the bypass pipe, 13b... lower end of the bypass pipe, 16
゜18...Partition room as a detection communication room, 16a
. 18a... Upper end of the partition, 16a, 18b...
Lower end of the partition. Representative Patent Attorney Masami Akimoto Diagram (G) Diagram 13b-・Paitsumatakan's Instigation Diagram Diagram

Claims (1)

[Claims] 1. In an oil tank in an oil-cooled compressor having a capacitive oil level detector, one end communicates with an air side separated by an appropriate distance from the oil level in the oil tank, and , forming a detection communication chamber whose other end communicates with the lubricating oil side separated by an appropriate distance from the oil surface;
An oil tank in an oil-cooled compressor, characterized in that the oil level detector is installed at a predetermined position of the detection communication chamber. 2. An oil tank in an oil-cooled compressor, characterized in that the detection communication chamber is constituted by a bypass pipe arranged on a side of the oil tank. 3. An oil tank in an oil-cooled compressor, wherein the detection communication chamber is defined by a part of the outer peripheral wall of the oil tank and a partition plate provided inside the oil tank. 4. An oil tank in an oil-cooled compressor, wherein the detection communication chamber is defined by a cylindrical partition plate provided inside the oil tank.