JPS6312524A - Pneumatic transport device - Google Patents

Abstract

PURPOSE:To ensure smooth transport of pulverized/granular substance by introducing compressed air into a transport pipe via an air takein means when a pressure tank is to be fed with compressed air in order to exhaust the pulverized/granular substance entirely, and thereby preventing blocking of transport pipe. CONSTITUTION:When a pulverized/granular substance is to be exhausted entirely from a pressure tank 1 and a transport pipe 14, a full exhaust button of a control circuit 43 is pushed. Now drive signals for solenoids 54a, 55a, 56a are given to open solenoid valves 54, 55, 56 to allow compressed air to be passed to an air takein device 70 from a compression tank 57 via a conduit P. This is made at a high speed near the sonic speed from a gap into the transport pipe 14, so that there is no risk for the substance transported afloat at high speed to intrude through the gap. Thus the air takein device 70 functions normally, and the transport pipe 14 is surely prevented from blocking during plug transportation of conduction, which should ensure smooth transport operations.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a pneumatic transport device for plug transporting granular material.

[Conventional technology and its problems]

Consisting of a sealed pressure tank and a transport pipe connected to it,
A pneumatic transport device is known in which the powder material discharged from the sealed pressure tank is accommodated in the transport pipe and transported by plug by supplying compressed air in pulses to the transport pipe. Plug transport means a pressure air layer (
Pulses) and powder aggregate layers (plugs) are formed alternately, and the action force of the pressurized air that passes through the plug due to the pressure difference between two pulses adjacent to the plug, that is, 1 wedge force is utilized. This is a method of propelling powder and granules by
For some reason, the transport pipe becomes clogged with powder and granular material, and as mentioned above, simply sending pulsed compressed air for normal transport will not be able to relieve the blockage, and eventually the transport action will stop. Resulting in.

In view of the above-mentioned problems, the present applicant has developed an air-tight pressure system for the purpose of providing a pneumatic conveying device u' that prevents the clogging of the granular material in the transport pipe and ensures continuous transport of the granular material. The granular material discharged from the sealed pressure tank is plug-transported along the transport pipe by supplying compressed air in pulses to a transport pipe connected to the tank, and at least one part of the transport pipe is provided. An air introduction means equipped with a pressure detection means is provided in the pipe to detect the total pressure inside the pipe at the location, and when this pressure is higher than a predetermined value, compressed air is introduced into the transport pipe via the air introduction means. We have proposed a pneumatic transport device that prevents clogging of powdery material in the transport pipe. However, when all of the powder material is completely discharged from the sealed pressure tank and transport pipe, air is generally introduced into the closed pressure tank to discharge the remaining amount, and this air flows at high speed inside the transport pipe.
When the particulate material is in a floating state, there is generally a gap in the air introduction means, and the particulate material tends to enter the recess or hollow space through the gap and accumulate there. In some cases, during normal plug transportation, the powdered material may become clogged, and even if all the air is sent through the air introduction means to prevent this, the flow rate will not reach the inside of the transportation pipe at a large flow rate.
It may not be possible to prevent occlusion. Furthermore, the pressure detection means may not operate and the purpose may not be achieved.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide an air transport device in which the air introduction means for preventing blockage can always operate normally.

[Means for solving problems]

The above object is to supply compressed air in pulses to a transport pipe connected to a closed pressure tank, thereby transporting the granular material discharged from the closed pressure tank along the transport pipe as a plug; At least one part of the transport pipe is provided with an air introduction means having a biased pressure detection means so as to detect the entire pressure inside the pipe at that part, and when this pressure is higher than a predetermined value, all of the air introduction means are valved to detect the pressure inside the transport pipe. In the compressed air transport device, the compressed air is introduced into the sealed pressure tank to completely prevent the blockage of the powder material in the transport pipe. This is achieved by an air transport device characterized in that when compressed air is introduced into the transport pipe, the compressed air is always introduced into the transport pipe via the air introduction means.

[For production]

During normal plug transportation, if the transport pipe is clogged with granular material, the pressure inside the pipe increases. This is detected by the pressure detection means. Based on this detection, compressed air is introduced into the transport pipe via R' during air introduction and acts to loosen the particulate material that is about to become clogged. Therefore, blockage is completely prevented.

When compressed air is introduced into the closed pressure tank to empty the closed pressure tank and the transport pipe, the particulate material is transported by air at high speed through the transport pipe in a loose powder state. At this time, compressed air is always introduced into the transport pipe via the air introduction means, so even if powdery material tries to accumulate in the recesses or hollow parts of the air introduction means, it will be immediately removed by the compressed air passing through it. It is removed and blown into the transport pipe. Therefore, the air introduction means can always function normally, and blockage in the transportation pipe during normal plug transportation can be reliably prevented. Further, the pressure detection means provided in the air introduction means can always accurately detect the pressure within the transport pipe where it is installed.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A pneumatic transportation device according to an embodiment of the present invention will be described below with reference to all the drawings.

In the figure, the pressure tank (1) has a main body (2) and a lid (3).
), the opening of the main body (2) is hermetically covered by a cover (3). A duct (4) is integrated with the lid (3).
) is formed, which consists of a lower pulp (5), an intermediate duct (
6), upper pulp (7), flexible joint (8)
) to the discharge opening of the hopper (9). The hopper (9) is supported on the ground via appropriate members.

It is connected to the discharge port (II is the discharge duct) C1η formed at the bottom of the main body (2) of the pressure tank (1), and this is connected to the air knife device (2) and the flexible joint (C13).
It is connected to a long transport pipe (b) through. Transport pipe CA4
1 is a rigid body rather than a 7-lexiple, but the collection tank (
I"i), and is supported on the ground by struts at appropriate locations. An air filter (g) is provided at the top of the collection tank (I71), and a valve is installed at the discharge opening. 4 are arranged and are opened and closed by an actuating device allGQ.

The pressure tank (1) is supported on the ground by a hinge 1211 similar to the -llI wall, and is supported on the ground by a load cell @ on the other gA wall side. That is, the total weight of the pressure tank (1) is 1tii due to the load cell. The pressure tank (1) is suspended from the ground by 7 lexipul joints (8) (2), and its total weight is the valve (5) (7), duct (4) (6) (I
I, 1. Load cell @1 with air knife device (2)
11. These and pressure tanks (
Since the weight of the main body (2) and lid body (3) of 1) is known in advance, the weight of the pressure tank (1) is determined from the output of the load cell.
) can know the weight of the powder material. In addition, a vibrator (c) is attached to the side wall of the pressure tank (1), and this vibration will cause the granular material to break if it does not form a bridge within the pressure tank (1). This allows the inside to maintain a good fluid state at all times.

Next, the piping system to the pressure tank (1) will be explained.

Compressed air is supplied to the upper part of the pressure tank (1) via a pipe G from a tank (to) serving as a compressed air source.

A valve is connected to the pipe (c), so that the pressure supplied to the pressure tank (1) can be adjusted to 0.000, for example, in terms of gauge pressure.
The pressure is adjusted to 5 to 0.6 atmospheres. Air flow rate is approximately 5rrv
/SeC. For this reason, the piping (c) is equipped with a flowmeter c! G and pressure gauge face are connected. The granular material in the pressure tank (1) is pressed downward as a whole by compressed air supplied to the upper part of the pressure tank (1) from the pressure tank (1).

From the piping [Yes], the piping ■ (branch) country μs) further branches off, and the piping c! A solenoid valve 6u is connected to ■, so that compressed air is supplied to the upper part of the pressure tank (1). When granular material is present, the electromagnetic valve (9) is closed and the above-mentioned valve (2) is open. To empty the pressure tank (1),
Then, when it is desired to completely discharge the granular material from the transport pipe (b), the electromagnetic valve q is opened, the above-mentioned valve (to) is closed, and the pressure is increased to a higher level, e.g., 15 to 20 V'.
Compressed air is sent into the pressure tank (1) at a flow rate of sec.

Branch piping 4 connects to the pressure tank (1) via the valve (351).
) is connected to the discharge port (10). The compressed air blown from this fluidizes the granular material present in the pressure tank (1), making it easy to discharge into the transport pipe (b). The flow rate and pressure of the compressed air are adjusted by the flow rate IT (to) and pressure needle (B) so that the compressed air is properly fluidized.

The branch pipes are connected to an air knife device (6) via a valve shaft and a solenoid valve (4G?).The air knife device (2), as is well known, blows out compressed air from a narrow gap on the outer periphery of the pipe. It acts like cutting all the part of the granular material with a knife.The electromagnetic valve +41 automatically repeats on and off and supplies pulsed compressed air.The pressure of this compressed air is determined by the flow rate field η and the pressure gauge. and the flow rate is adjusted accordingly.

Solenoid valve (5) (7) ■T41 solenoid part 4
) (4E9 Gυ (4υ are each connected to the output terminal of the control path (41).

Further, the output terminal of the load cell is connected to the input terminal of the control (GL path).

Furthermore, tank c! 41 is connected to the pressure gauge 04, and the tank c! It is assumed that the total pressure within the sludge is detected and compressed air is supplied from a compressor (not shown) to keep this pressure within a predetermined range.

As mentioned above, the transport pipe (b) extends from the flexible joint (2) to the collection tank aη,
Air introducers σC equipped with pressure detectors 6υ0521531 are provided at three locations, and the pressure in the corresponding pipes is detected by the detectors 61) 621 (g). Compressed air tank C57] is connected to piping 5Q (59
1 (601 and solenoid valve C541551 (561't
- Compressed air is supplied to the air introducer (7α) through the pressure detector (5υ (52153)) which generates an excitation signal when it detects a pressure above a predetermined value. To) Solenoid part (54a) of (8)
) (55a) and (56a) to open them. Solenoid part (54a) (55
1) (+568) is further connected to the output terminal of the control circuit (43).

FIG. 2 shows details of the air introducer qα, which will now be described.

As shown by the dotted line, the air introducer σα is connected to the above side transport pipe (b).
It is fixed by bolts or the like, although not shown, between the seventh rank part (14a) of 14a and the seventh rank part (tea) of the downstream transport pipe α fathom.

Air introducer (7) consists of two annular members σ11σ
゜Those central openings (71M) (72a) are transport pipes α4
The holes (14a) and (14b) are aligned with each other, and their inner diameters are the same.

A hole (7th) in which a pressure detector 621 (representatively shown; the same applies to other detectors Co11 C531) is installed and a compressed air supply hole (71C) are formed in the peripheral wall of one annular member συ. has been done. A conduit P for feeding compressed air is attached to the hole (71C). Annular member (71
) has a stepped hole, and an annular space a is formed between this and the other annular member (71).
) (Gap Q311t between both end faces of 7Z and inner annular member t71) (Central opening (71a) of 721 (72
a), that is, communicates with the inside of the hole (t4b) of the transport pipe α4. By passing through such a gap, the compressed air supplied from the hole (71c) in the annular member σ has a flow velocity further increased by the nozzle effect, and is introduced into the transport pipe α4 at a speed almost close to the speed of sound. Ru.

The present embodiment is configured as described above, and its operation will be explained next.

First, normal transportation conditions will be explained. Pressure tank (
1) Powder material is stored in the container above the lower limit level. This is detected by the load cell. That is, the specific gravity of the powder material is measured in advance, and the material level is calculated within the control circuit station from this value and the detected material weight. This result shows that the powder material exceeds the lower limit level in the pressure tank (1
) and the solenoid part (44115
C3υ is not excited, but a pulsed current is passed through the solenoid part (4υ) of the electromagnetic valve (41). That is, the electromagnetic valve +41 opens and closes 10 times to supply pulsed compressed air to the air knife device.

On the other hand, in the upper part of the pressure tank (1), compressed air is piped (
251, supplied through the valve (to) and pressure tank (
1) The granular material present within is pressed downwards as a whole. On the other hand, compressed air is also supplied from the discharge port Q (>) and the granular material is kept in a fluid state. It is inevitable that a bridge of the granular material will be formed in the pressure tank (1) due to the vibration of the vibrator 0. A good and uniform flow condition of the material is obtained.The tendency of material to adhere to the inner walls of the pressure tank (1) and form bridge gold is prevented.

The powder material flows smoothly from the pressure tank (1) into the duct aυ
and into the air knife device 111(2).

The continuously supplied granular material is divided by intermittent compressed air as if cut by a υ knife, and is transported through the transport pipe (b) in the form of a plug as shown in the figure. (4η is the powder material p, (4) 9 is air. Note that the air introducer ff
Although there is a gap TAB inside L, almost no powder material leaks from this space during plug transportation.

Powdered paulownia wood is collected in the collection tank (17), and the air passes through a filter and is exhausted to the outside. Filter (g)
This prevents the powder material from leaking to the outside.

When the load cell 021 detects that the granular material in the pressure tank (1) has decreased and reached a predetermined lower limit level, the control circuit (c) activates the solenoid parts (41 (441ffi) of the electromagnetic valves (5) and (7) alternately. All the signals to excite are generated.

That is, the upper solenoid valve (7) is opened and the hopper (
9), the granular material is discharged into the duct (6). child\
When a predetermined amount or a predetermined period of time is discharged, the solenoid part (441 is demagnetized and the solenoid valve (7
) is closed. Next, the electromagnetic valve (5) is connected to the solenoid part (
The granular material in the open side duct (6) is discharged into the pressure tank (1) when θ is excited. When the water is discharged for a predetermined period of time or when the duct (6) is empty, the solenoid part 1 is deenergized and the electromagnetic valve (5) is closed.

Next, the upper electromagnetic valve (7) is connected to the solenoid part (441
The p-opening is caused by the excitation of the hopper (9), and material is supplied from the hopper (9) into the duct (6).

As described above, the electromagnetic valves (5) and (7) are alternately opened and closed, and the granular material is replenished from the hopper (9) into the pressure tank (1) via the intermediate duct (6). Even during this replenishment, the material is continuously supplied from the pressure tank (1) to the transport pipe α◆, and the material is transported by a pulsed compressed air plug. Compressed air is continuously supplied to the upper part of the pressure tank (1) through the pipe G, but as mentioned above, this compressed air is supplied to the hopper ( 9) Exhaust into the atmosphere is prevented as much as possible.In other words, pressure loss during replenishment is prevented as much as possible.

When the t-load cell detects that the granular material in the pressure tank (1) has been supplied to the predetermined upper limit level, the alternate excitation of the electromagnetic valves (5) and (7) is stopped, and both pulps (5) are (7) is closed.

Next, we will explain the case where the pressure tank (1) is emptied and the powdered material is completely discharged from the transport pipe.

In this case, the complete discharge button provided in the control circuit (43) shall be pressed even though it is not shown in the figure.The load cell detects that the granular material in the pressure tank (1) has reached the lower limit level. In this case, 'mi valve (5) (n does not operate, solenoid valve (7) (4G solenoid part C31
) (4υ are respectively excited and demagnetized. In other words, the electromagnetic valve ■ opens and a large flow of compressed air is guided into the pressure tank (1). Also, the electromagnetic valve (40 is normally closed and the pulsed The supply of compressed air will be stopped.

Continuously high-pressure compressed air discharges the material in the pressure tank (1) into the transport pipe α, and the material in the transport pipe (b) is discharged into the collection tank a? by this compressed air. ) is discharged into the body. Furthermore, the amount of material adhering to the inner wall of the pressure tank (1) due to the vibration of the vibrator (c) is reduced as much as possible.

The powdery material is transported in a suspended state in the transport pipe (b), but in this example, the powdery material hardly enters into the space D due to the gap in the air introducer +71). .

That is, while pressing the complete ejection button, the control circuit (43
A drive signal is supplied from the solenoid parts (54a), (55a), and (56a). As a result, the electromagnetic valve t54
J5515fEl is opened and compressed air is supplied from the compressed air tank 6η to the air inlet f701 through the conduit Pf:. This is introduced from the gap (811) into the transportation pipe α Even if it tries to invade the space group in 17CI, it will not be suppressed and will not be able to do so.Therefore, the granular material is prevented from being blocked in space (2).

The granular material accumulated in the collection tank (l'i) is supplied to the next process by driving the actuating device 4 to open the valve 4.

In the above plug transportation, a case will be explained in which the powdered paulownia material flows through the transport pipe α4, and the powdered material may try to block somewhere in the transport pipe C141 for some reason. According to this embodiment, this can be prevented and a smooth flow can always be guaranteed.

Generally, granular materials tend to become clogged immediately before the curved portion of the transport pipe α◆, but let us now assume that no blockage occurs at the location where the pressure detector T5B is installed. Then, the pressure inside the pipe in this part increases, and when this exceeds a predetermined value, the pressure detector 6υ generates an excitation g1 signal, which is sent to the electromagnetic valve t54.
1 solenoid section (54a). As a result, the t-magnetic pulp system, which had been closed until now, is opened and compressed air is supplied from the p1 tank 6η via the pipe (581) to the pipe section where the pressure detector 5B is attached.

The compressed air loosens the particulate material that was about to become clogged, and it is smoothly transferred to the downstream side again. As a result, the pressure inside this pipe decreases to below the predetermined value again, the excitation signal of the pressure detector 6υ disappears, and the electromagnetic valve 541 closes again.

The above is an air introduction device (7Q1m) equipped with a pressure detector 6D.
Although a case has been described in which the particulate material is likely to block the area near where the pressure sensor is provided, blockage is similarly prevented at the location where the t53)ffi of other pressure detectors are provided. Please note that the air inlet device (
Since 701 is not clogged with powder material, the pressure can always be accurately detected by the total pressure detector.

The embodiments of the present invention have been described above, but of course the present invention is not limited thereto, and various modifications can be made based on the technical idea of the present invention.

For example, in the above embodiment, the air introducers (7α) for the pressure detectors 151) to C53 were provided at three locations on the transport pipe αΦ, but they may be further increased. Or they may be decreased, for example, at − locations. However, since there is a considerable time delay in the pressure propagation of the fluid, it is preferable to increase the total number of air introducers Ctα equipped with pressure detectors to prevent blockage from occurring at a certain point. If so, this can be immediately released.Also, as mentioned above, powder and granular materials tend to become clogged slightly upstream of the bend in the general transport pipe Q4, so place the pressure detector in such a location as much as possible. It is desirable to provide a biased 'fc air inlet box.

Further, the air introducing means is not limited to the one having the configuration shown in FIG. 2, and all known air introducing devices for this shield can be applied.

〔Effect of the invention〕

As described above, according to the pneumatic transport device of the present invention, the particulate material does not block the air introduction means, so that it is possible to reliably prevent any particulate material from clogging in the transport pipe, and to always keep the circle fW transportation can be guaranteed.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view of a pneumatic transport device according to an embodiment of the present invention, and FIG. 2 is an enlarged sectional view of the main part in FIG. 1. In the figure,

Claims (1)

[Claims] By supplying compressed air in pulses to a transport pipe connected to a closed pressure tank, the granular material discharged from the closed pressure tank is transported along the transport pipe as a plug, An air introduction means equipped with a pressure detection means is provided at least at one location to detect the pressure inside the pipe at the location, and when this pressure is higher than a predetermined value, compressed air is introduced into the transport pipe via the air introduction means. In the pneumatic conveying device, which prevents clogging of powdery material in the transport pipe by introducing compressed air into the sealed pressure tank to completely discharge the powdery material from the sealed pressure tank and the transport pipe. A pneumatic transportation device characterized in that compressed air is always introduced into the transport pipe via the air introduction means when the air is introduced.