JP2526242Y2 - Drain discharge device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drain discharge device, and more particularly, to a method for supplying compressed air from an air compressor (compressor) to an air tool or terminal equipment through a predetermined pipe. The present invention relates to an air dryer used for removing contained water and oil (drain) and the like, and to an apparatus for discharging drain generated by condensation and separation to the outside.

[0002]

2. Description of the Related Art Conventionally, this type of drain discharge device (hereinafter, referred to as "drain discharge device") has been proposed.
Among them, a float type is well known as a typical example of a so-called auto drain. This moves the float up and down by the buoyancy of the drain accumulated inside, and uses that movement to open and close the discharge port (discharge valve),
It is configured to automatically discharge drain.

[0003]

The conventional device of this type can automatically drain the drain, but the structure is liable to be complicated because a mechanically movable portion is provided in a valve opening / closing mechanism or the like. Therefore, there is a problem in reliability and durability of the device, such as a decrease in the discharge function or a failure easily caused by a foreign substance such as iron rust or dust accumulated in the device.

Further, these devices have a problem that when a certain amount of drain is discharged, the drain is discharged at a time under a pressurized state, so that it scatters and contaminates the surroundings, and the discharge noise is large. In addition, at the end of discharge, air (hereinafter, also referred to as gas) is discharged together with the drain, so that gas is wasted (pressure loss).

[0005] Under such circumstances, the present applicant has proposed a drain discharger (apparatus) using the bubble point pressure of a porous body. This is configured by providing a porous body having a bubble point pressure higher than the pressure of the gas received by the introduction port, in such a manner as to partition between the introduction port and the discharge port of the drain.

[0006] In this apparatus, in order to discharge (extrude) the drain permeated (absorbed) into the pores of the porous body and pass the gas, the gas pressure received at the inlet is determined by the drain pressure due to the capillary phenomenon. Pressure, that is, greater than the bubble point pressure of the porous body. According to this apparatus, as long as the gas pressure received at the inlet is smaller than the bubble point pressure of the porous body, the drain continuously penetrates into the pores of the porous body without causing gas leakage. It is extruded by the pressure difference between the inlet side and the outlet side, passes through the pores, and is continuously and automatically discharged from the outlet.

Therefore, although this device has a simple structure with no mechanical moving parts, it can discharge drain automatically and continuously, and there is no scattering or noise at the time of discharging. While having the excellent effect of, in principle,
The porous body must be wet, that is, the pores must be closed with a liquid (water or oil). If it is dry, the gas leaks through the pores and loses its function as an auto drain. That is, when the amount of drainage is extremely small or the porous body is not used for a long time (period) and the porous body is dried, there is a problem that a gas leak (pressure loss) occurs.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of a drain discharge device using a bubble point pressure of a porous body, and has as its object to provide a highly reliable apparatus that prevents drying of a porous body.

[0009]

In order to achieve the above object, the present invention is a drain discharge device for discharging drain contained in a compressed gas such as compressed air, in which a drain is introduced. A porous body is provided so as to partition between the mouth and the outlet, and the porous body has a bubble point pressure set to be higher than the pressure of the gas received by the inlet, and the porous body and the outlet And a drain member is provided in the drain reservoir so as to partition the porous body and the discharge port below the drain overflow surface of the discharge port. It is.

Here, the bubble point pressure P is a pressure determined by the relationship between the interfacial tension between the liquid, the porous body and the gas (air) and the pore diameter of the porous body, and is derived from the following equation. Incidentally, since the surface tension σ of the oil contained in such a gas is usually smaller than that of water, the bubble point pressure P is lower when the oil is impregnated than when the oil is impregnated. Therefore, even in that case, it is necessary to use a porous body having a bubble point pressure P that can sufficiently withstand the used gas pressure. P = K · 4πσ cos θ · 1 / d (K: correction coefficient of pore shape, σ: surface tension, θ: solid-liquid contact angle, d: pore diameter of porous body).

[0011]

According to the above construction, the drain inlet of the present apparatus is connected to, for example, the drain outlet of an air dryer, and when it is operated (operated), the drain generated by condensation and separation therefrom has a predetermined air pressure. While flowing into the apparatus. The inflowing drain penetrates into the pores of the porous body, and is pushed out by the air pressure, passes through, and accumulates in the drain reservoir. And the accumulated drain rises the liquid level and exceeds the overflow surface of the drain at the discharge port.
It is discharged outside in the form of overflow from the discharge port.

That is, when the porous body is wet due to the inflow of the drain into the apparatus, the bubble point pressure is set to be higher than the air pressure. Due to the pressure difference between the side and the outlet side, only the drain passes through the porous body and is continuously discharged to the outside.

After the start of the discharge, the drain that has passed through the porous body is discharged under the partition member of the drain reservoir, that is, through a portion communicating below the drain overflow surface of the discharge port. The water reaches the outlet side. At this time, the water has a higher specific gravity than the oil, so that it can preferentially dive.
Therefore, the inside of the partition member in the drain reservoir gradually increases in oil content, and is eventually substantially filled with oil. Then, if the operation of the air dryer is stopped in this state, the pressure difference between the inlet side and the outlet side disappears, and the oil inside the partition member is kept in contact with the porous body.

By the way, even if the stoppage is for a long time (period) and the internal water content is reduced by evaporation or the like, the reduction due to oil volatilization is very small. Therefore, even if the water permeating the porous body is reduced, the oil in contact therewith permeates and closes the pores. As a result, the porous body is kept substantially constantly in a wet state. Thus, even if the use of an air dryer or the like is interrupted for a long period of time, it is possible to effectively prevent the porous body from drying out, so that unexpected troubles such as gas leakage (pressure loss) can be avoided when the operation is resumed. Is done.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment Next, a first embodiment of the device according to the present invention will be described in detail with reference to FIG. In the figure, reference numeral 1 denotes an apparatus main body (simply referred to as a main body). A pair of left and right hat-shaped housings 1a and 1b are joined to flanges provided on the peripheral edges thereof to keep watertight as described later. A porous body 2 and a partition member 3 are incorporated therein, and bolts 4 and nuts 5 are tightened to form a drum shape. In this example, an inlet 6 is provided at the upper part of one housing (left side in FIG. 1) 1a for connecting a pipe to an air dryer (not shown) to introduce (flow) the drain into the main body 1, and on the other side (right side in FIG. 1). Has a discharge port 7 for discharging the drain at substantially the same level.

On the other hand, a concave portion is provided on the inner peripheral edge of the flange of the main body 1, and the concave portion is provided in the concave portion through an annular packing 8.
A disc-shaped porous body 2 made of ceramic, which will be described later, is provided so as to be vertically partitioned along the mating surface. The inside of the porous body 2 is divided into right and left, and the left side is a drain receiving space U and the right side is a drain reservoir T. On the side of the drain reservoir T, a partitioning member 3 formed in the shape of a dish has its convex portion directed outward (toward the discharge port 7) in the middle portion, and its peripheral flange formed in the concave portion via the packings 8,8. It is provided by fitting. However,
The partition member 3 in this example is provided with an opening 3a below, and connects the left and right spaces of the drain reservoir T. In this example, an opening 3b of an appropriate size is provided above the partitioning member 3 above the overflow surface A of the discharge port 7 as air bleeding or excess oil bleeding.

By the way, the bubble point pressure of the porous body must be higher than the pressure of the gas received by the inlet. Here, an example of the method of manufacturing the disk-shaped material used in this embodiment will be described.

First, a slurry of the following two types of alumina, A and B, is prepared. A: Alumina (purity 99.9%, average particle size 1.2 μm)
150 g, 18 g of carboxymethylcellulose, 1.5 g of a polycarboxylic acid-based surfactant, and 830 ml of water mixed and ground using an alumina pot and alumina spheroid. B: Alumina (purity 99.9%, average particle size 0.4 μm)
150 g, carboxymethyl cellulose 10.5 g, polycarboxylic acid surfactant 1.5 g, water 840 ml,
A mixture obtained by mixing and grinding using an alumina pot and alumina sphere.

Next, the slurry A was made to have an average pore diameter of 3.4 μm.
And dried and fired at 1400 ° C. for 2 hours to form a thin film. Thereafter, the slurry B was further applied to the substrate, dried, and dried at 1300 ° C. for 2 hours.
Baking for a time to form a thin film. Then, in order to repair this film, the slurry B is again applied to the substrate in the same manner as above, dried and fired at 1300 ° C. for 2 hours to further bake the thin film.

The bubble point pressure of the porous body 2 manufactured in this manner and used in this example is about 12
kg / cm ² , and about 5.5 kg / cm ² with respect to compressor oil (trade name: oil for Hitachi Bavicon).

Next, the operation or effect of the apparatus of this embodiment will be described. However, the porous body 2 is maintained in a wet or infiltrated state by being immersed in water in advance, and the pores are in a state closed with water. When a refrigeration air dryer (not shown) is operated (air pressure is set to 5 kg / cm ² or less) and the drain flows into the drain receiving space U, the drain penetrates into the pores of the porous body 2 by capillary action,
The air passes through the porous body 2 so as to be gradually extruded by air pressure, and accumulates in the drain reservoir T. So drain
The liquid level is raised and exceeds the drain overflow surface A of the discharge port 7,
Is discharged. The arrows in the figure indicate the drain flow.
In such an operation, since the bubble point pressure of the porous body 2 is larger than the air pressure, only the drain is discharged through the porous body 2 and no gas leakage occurs.

By the way, the behavior of the drain after passing through the porous body 2 reaches the discharge port 7 side so as to pass through the opening 3a below the partition member 3. At this time, water sinks preferentially over oil. Therefore, the inside (porous body side) of the partition member 3 is gradually filled with oil. And
The oil and water are separated into two upper and lower layers. The liquid level on the inner side of the partition member 3 becomes higher due to the pressure difference due to the larger amount of oil than on the outer side, and flows into the discharge port 7 as excess oil at the upper opening 3b level as shown by the two-dot chain line in the figure. Is discharged.

In this way, when the partition member 3 is used for a certain time, the inside of the partition member 3 is filled with the oil component O, and the porous body 2 is in a state of being in positive contact with the oil O. As a result, if the operation of the air dryer is stopped and the water in the porous body 2 and the drain reservoir T evaporates and decreases, the oil O penetrates into the pores accordingly. Without draining, only drain is automatically and continuously discharged.

In this embodiment, at the start of operation, the pores are closed by immersing the porous body 2 in water in advance, but an appropriate oil is initially sealed in the inside of the apparatus on the outlet 7 side (drain reservoir T). You may keep it. With this arrangement, the upper opening 3b of the partition member 3 is not particularly required.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. 2 and 3. In this embodiment, the drain is roughly converted into water and oil. It is separated and discharged to the outside, so to say it is an improvement of the previous example,
The following describes mainly the improvements or differences.

In this embodiment, the main body 11 is formed in a cylindrical shape with a bottom, and a lid 12 is attached to the upper part of the O.sub.
It is airtightly fitted through the ring packing 13 and
The cap nut 14 is screwed by engaging a flange provided on the outer periphery of the upper end of the main body 11 with the outer periphery of the lower part of the main body 11, and the lid 12 is fixed to the main body 11. A drain inlet 15 is provided on one side (left side in FIG. 2) of the lid 12, and opens from the lower end through the conduit 16 to the central lower surface. In this example, the inlet 15 is formed with a pipe taper thread for connecting to an air dryer (not shown).

On the lower surface of the lid 12, a ceramic porous body 17 formed in a cylindrical shape is disposed in a hanging manner at upper and lower end portions via ring packings 18, 18, and the lower end surface side is disposed. The upper surface of the disk-shaped flange 19 is held in a lifted state, a bolt 20 is passed through the center hole as a tie rod, and the screw is screwed into a screw hole in the lower center of the lid 12.
2 and porous body 17, and further, porous body 17 and flange 19
Is kept airtight. And this porous body 1
A partitioning member 21 formed in a cylindrical shape is vertically provided on the lower surface of the lid 12 so as to be concentric with the base 7 and substantially at the middle between the inside of the main body 11 and the outside of the porous body 17. However, in this example, the height is set to be the same as that of the porous body 17.

On the other hand, discharge pipes 22 and 23 are provided on the outside of the partition member 21 with a slight gap above the upper end thereof, and penetrate the lower end thereof while keeping the bottom of the main body 11 tightly closed. , Arranged vertically. However, the outer discharge pipe 23 is for discharging the drain mainly composed of water as described later, and the inner one is for discharging the drain mainly composed of oil. The outlets 22a and 23a are provided. In addition, the outer discharge pipe 2
The upper end surface of No. 3, that is, the overflow surface A is slightly lower than that on the inner side.

As a result, in this embodiment, the porous body 17 is provided so that the inside of the main body 11 partitions the inlet 15 from the outlets 22a and 23a, and the inside of the porous body 17 is a drain receiving space. U, and the outside and lower part of the porous body 17 are drain reservoirs T.

Also in this embodiment, when the drain flows into the drain receiving space U inside the porous body 17, it continuously penetrates into the pores of the porous body 17 by capillary action and is gradually extruded by air pressure. The porous body 17
And then accumulates in a drain reservoir T on the outside or bottom thereof.
Then, the drain rises its liquid level in accordance with the inflow, and is discharged from the portion exceeding the level of the discharge port 23 a (the drain overflow surface A) of the discharge pipe 23 outside the partition member 21.

The drain that has passed through the porous body 17 is
Since the partition member 21 is provided, it passes through the lower edge and reaches the outer discharge port 23a side. In the process, the water is separated into the lower layer and the oil is separated into the upper layer due to the difference in specific gravity. The oil is accumulated in the reservoir T, but the oil is
It is difficult to dive underneath, so the partition member 2
1 gradually increases in oil content, and is eventually substantially filled with oil content O. Therefore, the porous body 17 has a large amount of oil content O
Is in contact with Although the liquid level of the oil component O on the inner side becomes higher, the oil component O is discharged from the portion exceeding the level (overflow surface) of the discharge port 22a of the inner discharge pipe 22.

Thus, a drain mainly composed of water is separated from the outer discharge pipe 23, and a drain mainly composed of oil is separated from the inner discharge pipe 22, respectively. Drops or flows down and is discharged.

Also in this embodiment, as in the previous embodiment, when operating as an auto drain, as long as the air pressure is smaller than the bubble point pressure of the porous body 17, no gas leakage occurs, and the porous body 17 Since it is in a state of being wetted with oil, it does not dry out even if use is interrupted for a long time, and gas leakage is effectively prevented.

In this embodiment, since the water and the oil can be positively separated and separately discharged, the subsequent drain treatment is facilitated. A normal drain has less oil than water, but is particularly suitable for a drain that contains a lot of oil.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIG. 4. This embodiment is different from the previous embodiment in that a cylindrical porous body 37 is provided. The difference is that the outside is a drain receiving space U, and the inside is a drain reservoir T. However, the difference is centered on the point that the water and oil can be separately discharged. Will be described.

In this embodiment, as in the previous embodiment, the bottomed cylindrical body 3
1, a lid 32 is internally fitted via an O-ring packing 33,
The cap nut 34 is fixed to the main body 31 by screwing. On one side (left side in FIG. 4) of the lid 32, a drain inlet 35 is provided, and on the right side, an outlet 36 for discharging oil (drain mainly composed of oil) is provided. ing.

A hollow tie rod 41 is screwed into the center of the lower surface of the lid 32, and a discharge pipe 43 for discharging moisture (drain mainly composed of water) is described below. It is interpolated while maintaining watertightness from below. In the present example, the tie rod 41 forms a partition member. Outside the tie rod (hereinafter, referred to as a partition member) 41, a concentric cylindrical porous body 37 is provided.
The upper and lower end portions are arranged via ring packings 38, 38, the lower end portion is held by a disk-shaped flange 39, and the threaded portion at the lower part of the tie rod is passed through the center hole, and the nut 42 is screwed. Thus, the lid 32 and the porous body 37, and the porous body 37 and the flange 39 are set in an airtight manner.
Although not shown, a proper sealing material is applied to the lower thread portion of the partition member 41 to maintain watertightness with the flange 39.

On the other hand, the partition member 41 has an opening 4 at the bottom.
1a is provided, while the discharge pipe 43 is inserted inside, as described above, to hold a slight gap above the upper end,
The lower end portion is disposed in a penetrating manner while keeping the center of the bottom of the main body 31 airtight. Thus, the drain T is formed inside the porous body 37 and outside the discharge pipe 43, and the discharge pipe 4 is formed.
Although the upper end of 3 is a discharge port 43a, its upper end surface (overflow surface A) is set slightly below that of the oil discharge port 36.

When the drain flows into the drain receiving space U, the liquid level rises, penetrates the porous body 37, passes through the porous body 37, and accumulates in the drain reservoir T on the inside. Through the lower opening 41a, the liquid overflows from the portion exceeding the upper surface level (the drain overflow surface A) of the discharge port 43a of the inner discharge pipe 43, and is dropped or discharged as indicated by the arrow in the drawing. At this time, the drain that has passed through the porous body 37 passes through the opening 41a and reaches the discharge port 43a. However, since the oil does not easily dive, the outside of the partition member 41 is substantially filled with the oil O when continuously used, Therefore, the porous body 37 is in a state of contacting a large amount of oil. The oil component O is discharged to the outside when the liquid level rises and exceeds the overflow surface level of the discharge port 36.

In this embodiment, since the outside of the cylindrical porous body 37 is the drain receiving space U (inlet side), the porous body 3
7 is pressed from the outer periphery. Therefore, it is suitable for a material such as ceramics having a tensile strength lower than a compressive strength.

The porous body used in each of the above embodiments is made of ceramic, but is not limited to this. Depending on the purpose and use of the device, it will be appropriately selected and used.However, in order to improve the discharge efficiency, it is necessary to have an affinity with the drain and to easily penetrate the pores. preferable. The average pore diameter and porosity may be appropriately selected and used depending on the gas pressure, bubble point pressure and the like.

The partition member should be made of a material through which oil does not permeate (permeate), such as a stainless steel plate, in order to allow oil to efficiently contact the porous body.
If a certain degree of performance deterioration can be tolerated, the material may not be a material capable of completely shutting off the inside and outside. For example, it is possible to use a porous material or a material formed like a fine mesh network.

Further, a portion formed below an overflow surface of a discharge port (a water discharge port in a case where water and oil are separated and discharged) and communicating the porous body with the discharge port is a unit. Although it depends on the drain flow rate per hour, a partition member is preferably provided so as to be as low as possible. By doing so, it is easy to hold oil inside the partition member (on the side of the porous body).

In the above-described embodiment, the case where the present apparatus is mounted on an air dryer is exemplified. However, the present apparatus is mounted on various air apparatuses using compressed air as a power source, such as an air brake system, or pneumatic piping. Needless to say, it can be used. Of course, the applicable compressed gas is not limited to air only.

[0045]

As is apparent from the above description, since the drain discharge device according to the present invention is an auto drain using the bubble point pressure of the porous body, it operates as an auto drain with a simple structure. In addition, gas leakage is effectively prevented during operation as an automatic drain, so that there is no waste of gas (pressure loss), and thus noise can be effectively prevented. Further, since the drain is continuously discharged, it is not scattered, which is effective in preventing surrounding contamination.

In addition, since the oil can be retained inside the partition member, the operation as the device is stopped,
Even if the water content decreases, the oil in contact blocks the pores of the porous body. Therefore, even when the operation is started, it is effective to prevent the occurrence of troubles such as gas leakage (pressure loss), and the reliability of the device can be improved.

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional front view showing a first embodiment of a drain discharge device according to the present invention.

FIG. 2 is a central longitudinal sectional front view showing a second embodiment of the drain discharge device according to the present invention.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a central vertical sectional front view showing a third embodiment of the drain discharge device according to the present invention.

[Explanation of symbols]

 1, 11, 31 Drain discharge device main body 2, 17, 37 Porous body 3, 21, 41 Partition member 6, 15, 35 Inlet 7, 23a, 43a Outlet T Drain reservoir A Drain overflow surface of outlet

Claims (1)

(57) [Scope of request for utility model registration] 1. A drain discharge device for discharging drain contained in a compressed gas such as compressed air, wherein a porous body is provided inside the drain discharge device to partition between a drain inlet and a drain. Along with the porous body, the bubble point pressure is set to be higher than the pressure of the gas received by the introduction port, and a drain reservoir is provided between the porous body and the discharge port. A drain discharge device, comprising a partition member that partitions the porous body and the discharge port below the drain overflow surface of the discharge port.