JP2973306B2 - Method and safety device for preventing compressed air from being released from electric drain trap - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a safety device for preventing the discharge of compressed air from an electric drain trap, and more particularly to a method for preventing the discharge of compressed air by an electric drain trap for some reason. The purpose of the present invention is to prevent the supply of compressed air from being hindered.

[0002]

2. Description of the Related Art Compressed air is used as an air source for various pneumatic machines, such as compressed air drills, nut runners, rivets, rock drills, underground drills, air hammers, air turbines, etc. The air compression device created was used. The air compressor that constitutes such an air compressor has reduced fluctuations in air pressure by temporarily storing compressed air in an air tank.

On the other hand, an air compressor is supplied with oil for lubrication. Therefore, the discharged compressed air contains oil and oil sludge obtained by burning the oil together with water.
If this oil or the oil sludge from which the oil is burned is discharged from the air tank as it is and used as an air source for various pneumatic equipment, the components that make up the pneumatic machine may become clogged with dust, etc. Was causing the problem. Therefore, the drain collected at the bottom of the air tank was connected to an electric drain trap through a drain hole at the bottom of the air tank via a pipe, and the drain collected from the drain trap was discharged every predetermined time. .

A conventional electric drain trap has a structure shown in FIG. 2 showing a closed state of the electric drain trap according to the present invention, and FIG. 3 showing an open state of the electric drain trap according to the present invention. It has the same configuration as the figure showing the state, and uses a direct acting solenoid valve.

FIG. 2 shows a state in which the coil 26 is not energized. The contact portion 23k of the plunger 23 is actuated by a spring 30 provided between the cylinder 32 and the plunger 23. Seat 21a of main body 21
Contact with the central discharge passage 21 of the valve body 21.
Fig. 3 shows a structure for bringing f into a closed state.

FIG. 3 shows a state in which the coil 26 is energized, and the coil 26 acting on the plunger 23.
2 shows a structure in which the plunger 23 is moved upward by a magnetic force from the valve body 21 so that the central discharge passage 21f of the valve body 21 is opened, and the drain is discharged from the inlet 21e of the valve body 21 to the outlet 21g.

Here, the valve body 21 and the cylinder 32 are integrally connected by screwing, and an O-ring 2
2, a closed flow path is formed.
Further, the coil 26 is sandwiched between the ring core stator 24 and the ring core wafer 25, and its outer periphery is covered with a coil case 27.
A nut 31 is fixed to an upper portion of the cylinder 32 on the opposite side of the valve body 21 between the cylinder 1 and the cylinder 32.

In this case, the operating force due to the energization of the coil 26 includes a force caused by a drain pressure acting on the outer diameter cross-sectional area of the seat 21a around the center discharge passage 21f of the valve body 21, a spring force caused by the spring 30, and a plunger. More force was required than the sum of the 23 weights. Therefore, in order to reduce the size of the coil 26 that generates the electromagnetic force,
The inner diameter of the central discharge passage 21f of the valve body 21 is 1 mm to 3 mm. The valve body 2
The inner diameter of one central discharge channel 21f is 1.5 mm to 10 mm.
Some catalogs show the size in mm.

[0009]

However, such a conventional method for preventing the release of compressed air and a safety device for an electric drain trap have the following problems. First, with the valve open, the coils 26 ...
・ Electrical systems such as the above failed, causing air to be released.

Second, when the plunger 23 is moved by the magnetic force from the coil 26 to open and close the valve, foreign matter such as dust stops moving the plunger 23 and the valve remains open. In some cases, air was released. An object of the present invention is to solve such a problem.

[0011]

According to the present invention, there is provided a method for preventing the compressed air from being discharged from an electric drain trap comprising an electromagnetic valve 20.
0 is kept open so that the amount of compressed air released from the solenoid valve 20 is smaller than the amount of compressed air produced by the air compressor 3.
It is characterized in that the flow path to the outflow port 21g of 0 or the communicating portion is narrowed.

Further, in the safety device for the electric drain trap constituted by the solenoid valve 20, any trouble may occur.
Therefore, when the solenoid valve 20 is kept open, air
From the amount of compressed air produced by the compressor 3,
The amount of compressed air released from the solenoid valve 20 is smaller.
Thus, the flow path leading to the outlet 21g of the solenoid valve 20,
Is characterized in that the communication part is narrowed .

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method and a safety device for preventing compressed air from being discharged from an electric drain trap according to the present invention will be described in detail with reference to the drawings. FIG. 1 is an overall configuration diagram in which an electric drain trap according to the present invention is provided, FIG. 2 is a diagram showing a closed state of the electric drain trap according to the present invention, and FIG. FIG. 2 is a view showing an open state of an electric drain trap according to the first embodiment.

FIG. 1 shows an air compressor 1 that takes in air from an air inlet 9 and transmits the rotation of a motor 4 to an air compressor 3 via a belt device 6 to store air in an air tank 2. Air tank 2 of compression device 1
The drain 10 collected at the bottom is supplied to a solenoid valve 20 through a pipe through a drain hole 7 below the air tank 2 and a strainer 8.
, While the solenoid valve 20 is operated by the timer 11. In this case, the electromagnetic drain 20, the strainer 8, and the timer 11 constitute an electric drain trap 50.

However, the solenoid valve 2 related to the method and the safety device for preventing compressed air from being discharged from the electric drain trap of the present invention.
The arrangement of 0 is not limited to the arrangement shown in FIG. 1, but may be of any shape as long as it is arranged for discharging the drain in the air circuit without being limited to FIG.

On the other hand, in FIGS. 2 and 3, the construction of the individual parts of the solenoid valve 20 shown in each drawing is the same as that of the prior art except for the shape. Is omitted here.

Here, the major difference from the prior art is that the central exhaust passage 21 of the valve body 21 constituting the solenoid valve 20 is different.
The ideal diameter of f is set to the value shown in the following (Table 1) according to the capacity of the motor 4 constituting the air compressor 1.

(Table 1) Configuration of the air compression device Compressed air generation amount Compressed air pressure Center discharge channel capacity of the motor of the valve body (KW) (l / min) (Kg / cm ² ) Inner diameter (mm) 0.75 75 7-9 0.7-0.9 1.5 150 １．１ 1.1-1.3 2.2 235 〃 1.3-1.6 3.7 400 １ 1.7-2.1 5.5 600 ２．１ 2.1 to 2.5

In this case, the central discharge passage 21 of the valve body 21
As the inner diameter of f approaches the lower limit value, the amount of compressed air to be discharged is more effective with respect to the release and release of compressed air.
Further, the closer the upper limit value is, the more the amount of the compressed air generated by the air compressor 3 and the amount of the compressed air discharged from the solenoid valve 20 are set to be substantially equal.

However, in the case of a small model such as 0.75 KW, if the inside diameter is too small, foreign matter such as dust may be clogged in the central discharge passage 21f. The following values are not effective: On the other hand, 1.5
For models of KW or more, reducing the inner diameter by about 30% is effective in reducing the amount of compressed air to be discharged, but other purposes such as discharging drain, etc. From the balance with parts, it can be said that the limit is about 20%.

From the above points, as a whole, the solenoid valve 20
The best value of the inner diameter of the central discharge channel 21f of the valve body 21 constituting the above is 2.3 mm or less (the average value of the upper and lower limits of the inner diameter of the central discharge channel 21f) and 0.7 mm or more.
However, for a model of 1.5 KW or more, another value can be set according to the above contents.

Although the above contents are not shown, the inside diameter of the inlet 21e or the outlet 21g of the valve body 21 constituting the solenoid valve 20 is not more than 2.5 mm.
A nipple provided with an orifice of 7 mm or more may be provided.

The method and the safety device for preventing the discharge of compressed air from the electric drain trap according to the present invention are configured as described above, and the operation thereof will be described below.

Generally, a drain trap is installed by connecting to the bottom of a drain generating device such as an air tank, an after cooler, an air cooler, etc.
Drain generated from these devices first flows into the drain trap strainer. The drain flowing from the air tank 2 to the electric drain trap 50 will be described below.

First, when the motor 4 starts rotating, the air compressor 3 is operated via the belt device 6, and when the compressed air is stored in the air tank 2 until a constant pressure is reached, the motor 4 stops. Therefore, the compressed air stored in the air tank 2 is supplied from a compressed air outlet 5 to a pipe (not shown).
Through the air cylinders, air motors, etc.
When the compressed air in the air tank 2 becomes equal to or less than a predetermined amount, the motor 4 is driven to replenish the air in the air tank 2, increase the air pressure, and stop.

Then, due to the compression of the air, the oil and water contained in the air are condensed and separated, and accumulate at the bottom of the air tank 2 as a drain 10 in which oil and water are mixed. This drain 10
Is connected to the solenoid valve 20 through the drain hole 7 through the strainer 8.
And after a certain period of time, is discharged to the outside as drain by a signal from the timer 11. However,
Although not shown in the drawings, a method in which the drain is discharged to the outside when the amount of the drain reaches a certain amount can be considered.

The drain entering the solenoid valve 20 is shown in FIG.
As shown in FIG. 2, at the position passing through the inlet 21 e of the valve body 21, the contact portion 23 k disposed at the tip of the plunger 23 pressed by the spring 30 and the seat 2 of the valve body 21
The flow is interrupted by the close contact of the flow path 1a. That is, in this case, the coil 26 is not energized.

Thereafter, when a certain time has elapsed, the coil 26 is energized, and the plunger 23 is actuated by an electromagnetic force.
This causes the plunger 23 to move upward, as shown in FIG.
A gap is formed between the valve body 21 and the seat 21 a of the valve body 21, and the drain that has been blocked is discharged to the outside through the gap, the central discharge passage 21 f of the valve body 21, and the outlet 21 g of the valve body 21. .

In this case, the plunger 23 does not operate due to troubles such as an electric system, foreign matter such as dust, etc., and the contact portion 23k below the plunger 23 and the seat 21a of the valve body 21 are closed. When it is left as it is,
When the central discharge passage 21f of the valve body 21 is clogged by foreign matter such as dust, the drain is not discharged,
There is no problem with using compressed air for the time being.

On the other hand, foreign matter such as an electric system,
When the plunger 23 does not operate due to a trouble such as... And the contact portion 23k under the plunger 23 and the seat 21a of the valve body 21 remain open, compressed air is discharged after draining. There was a problem that the air was left in a state of being discharged and the compressed air could not be used.

In the present invention, the size of the inner diameter of the central discharge passage 21f of the valve body 21
Even when the lower contact portion 23k and the seat 21a of the valve main body 21 are opened, the amount of compressed air discharged from the central discharge passage 21f of the main body 21 is produced by the air compressor 3. That is, it is set to be smaller than the amount of compressed air. This solves the immediate problem of using compressed air. This means that, similarly to the case where the center discharge passage 21f of the main body 21 is throttled, a nipple narrowed by an orifice is disposed in a passage reaching the outlet 21g of the solenoid valve 20 or a communication portion. However, the same effect can be obtained.

The inner diameter of the central discharge passage 21f of the main body 21 is not only reduced by reducing the inner diameter to reduce the amount of compressed air discharged, but also by foreign substances such as dust and the like. The size of 26 and the size of the solenoid valve 20 ...
And so on, taking into account various factors.

[0033]

As is clear from the above description, the following effects can be obtained by the present invention. That is, even when the contact portion 23k of the lower portion of the plunger 23 and the seat 21a of the valve body 21 are opened, the amount of compressed air discharged from the central discharge passage 21f of the body 21 is larger than that of the air compressor 3. By setting the amount to be smaller than the amount of compressed air created by the above, it is possible to always use the compressed air even when the solenoid valve 20 is left open.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram in which an electric drain trap according to the present invention is provided.

FIG. 2 is a diagram showing a closed state of the electric drain trap according to the present invention.

FIG. 3 shows an open state of the electric drain trap according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Air compressor 2 ... Air tank 3 ... Air compressor 4 ... Motor 5 ... Compressed air outlet 6. ····· Belt device 7 ····· Drain bleed hole 8 ··················· Strainer 9 ·················· Drain 11 ······ Timer 12 Power supply 20 Electromagnetic valve 21 Valve body 21a Seat 21e Inlet 21f Central discharge channel 21g Flow Outlet 22 ····· O-ring 23 ···· Plunger 23k ··· Contact part 24 ···· Ring core stator 25 ···· Ring core waist 26 ···· Coil 27 ··· .... Coil case 30 ... Spring 31 ... Nut 32 ... Cylinder 50 ... ..Electric drain traps

Claims (2)

(57) [Claims] In the method for preventing compressed air from being discharged from an electric drain trap constituted by an electromagnetic valve (20), when the electromagnetic valve (20) is kept open due to some trouble, the air compressor (3). A flow path or communication with the outlet (21g) of the solenoid valve (20) such that the amount of compressed air released from the solenoid valve (20) is smaller than the amount of compressed air created by the solenoid valve (20). A method for preventing compressed air from being released from an electric drain trap, characterized in that the portion is squeezed. 2. In a safety device for an electric drain trap constituted by an electromagnetic valve (20), any trouble may occur.
Thus, when the solenoid valve (20) is left open,
The amount of compressed air produced by the air compressor (3)
The amount of compressed air released from the solenoid valve (20)
So that the outlet (21) of the solenoid valve (20) is smaller.
A safety device for an electric drain trap, characterized in that a flow path leading to g) or a communication portion is narrowed .