JPH0420836Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) The present invention relates to a pneumatic transport device for powder and granule, which fills a blow tank with powder and granules and transports the powder through a transport pipe using high-pressure air.

(Prior art) When transporting powder or granular material using high-pressure air, the main air is made to flow into the blow tank through the main air pipe, and additional air is branched from the main air pipe and connected to the transport pipe. flow into the transport pipe through the pipe,
A method for smoothly transporting powder or granules by air is known.

In the above transportation method, the flow rate of the main air is controlled by the flow rate adjustment valve to the necessary and sufficient level to maintain the internal pressure of the blow tank at a steady transportation pressure (the optimal pressure for transporting the powder and granules in the blow tank). Therefore, at the beginning of transportation, it takes a long time for the blow tank to reach steady transportation pressure (pump-up time), resulting in a problem of poor transportation efficiency.

Conventionally, in order to solve the above problems, pump-up air piping was provided separately from the transportation air piping, and additional air piping in the transportation piping was opened and closed by the pressure inside the blow tank (Japanese Patent Publication No. 1973- (No. 19994) to reduce pump-up time. However, these methods require an electric control mechanism including a blow tank pressure sensor and a line switch, resulting in a complicated configuration and troublesome adjustment and maintenance.

(Purpose of the invention) The present invention was made in view of the above-mentioned circumstances, and aims to shorten the pump-up time at the beginning of transportation using a simple mechanism.

(Structure of the invention) Hereinafter, the present invention will be described in detail based on an example. In FIG. 2 is connected to the tank 1, and a powder transport pipe 3 is connected to the bottom opening of the tank 1. A cone valve 4 is provided at the outlet of the granular powder supply pipe 2, and the valve 4 is connected to a valve drive device 5 via a link mechanism, and is raised and lowered by the operation of the drive device 5. Accordingly, the powder supply pipe 2 is opened and closed.

The blow tank 1 communicates with a high-pressure air source 7 via a main air pipe 6, and the main air pipe 6 can be opened and closed by an air supply valve 8. An additional air pipe 9 branches from a position downstream of the air supply valve 8 in the main air pipe 6, and the tip of the additional air pipe 9 is connected to the transport pipe 3. Note that 11 is a flow rate adjustment valve, and 12 is a check valve. A pressure reducing valve 13 is attached to the main air pipe 6 at a position downstream from the branch point with the additional air pipe 9. Note that 14 is a check valve.

(Function) In the device configured as described above, the set pressure of the pressure reducing valve 13 of the main air pipe 6 is set to a value slightly higher than the steady transport pressure of the blow tank 1,
Further, the flow rate adjustment valve 11 of the additional air pipe 9 is adjusted to an appropriate flow rate. Thereafter, when a predetermined amount of powder is supplied into the blow tank 1 through the powder supply pipe 2 and the air supply valve 8 is opened, high pressure air is supplied from the high pressure air source 7 to the main air pipe. 6 to the blow tank 1 side, and on the other hand to the transport pipe 3 side via the additional air pipe 9. At this time, since the pressure inside the blow tank 1 is much lower than the set pressure of the pressure reducing valve 13, the opening degree of the valve 13 is expanded by the action of the diaphragm in the pressure reducing valve 13, and a large amount of high pressure air flows into the blow tank. flow inward.

As the pressure inside the blow tank 1 increases, the opening degree of the pressure reducing valve 13 gradually decreases due to the action of the diaphragm in the pressure reducing valve 13, and the amount of high pressure air flowing into the blow tank 1 decreases. When the internal pressure of the blow tank 1 eventually reaches the steady transport pressure, the powder inside is pushed out to the transport pipe 3 by the pressure. This causes a loss in the pressure inside the blow tank 1, but the opening degree of the pressure reducing valve 13 increases by the amount of the loss and increases the amount of high pressure air flowing in, so the internal pressure of the blow tank 1 is always maintained at a steady state. The pressure is maintained, and as a result, the powder and granules are continuously delivered to the three portions of the transport pipe in fixed quantities.

(Effects of the invention) As is clear from the above explanation, the present invention is a device for pneumatic transportation of powder and granular materials in which a pressure reducing valve 13 is attached to the main air pipe 6 that communicates the blow tank 1 and the high-pressure air source 7. be. According to the present invention, a large amount of high-pressure air is supplied into the blow tank 1 at the beginning of the transportation of powder and granules, and the blow tank 1
The time required for the pump to reach steady transport pressure (pump-up time) is shortened. Further, once the internal pressure of the blow tank 1 reaches the steady transport pressure, high-pressure air is continuously supplied in an amount necessary to continuously transport the powder and granules. In other words, work that conventionally required a blow tank pressure detector, a pipeline switch, and an electrical control mechanism for these can now be done with a single pressure reducing valve, simplifying the configuration and requiring less adjustment and maintenance. becomes easier.

In the above embodiment, the pressure reducing valve 13 is provided in the main air pipe 6.
is installed, and the supply of high-pressure air into the blow tank 1 is controlled only by the pressure reducing valve 13. However, as shown in FIG. A bypass pipe 15 is provided located at
The flow rate adjustment in step 5 may be performed using a conventional flow rate adjustment valve 16.

In this case, the set pressure of the pressure reducing valve 13 is made equal to the steady transport pressure of the blow tank 1, and the set flow rate of the flow rate regulating valve 16 is set to a value necessary and sufficient to maintain the steady transport pressure.

In such a configuration, when the air supply valve 8 is opened, the high pressure air supplied from the high pressure air source 7 flows into the blow tank 1 via both the main air pipe 6 and the bypass pipe 15. Therefore, the pump-up time is shorter than in the first embodiment. As the pressure inside the blow tank 1 rises, the opening degree of the pressure reducing valve 13 gradually decreases, and when the internal pressure of the blow tank 1 eventually reaches the steady transport pressure, the pressure reducing valve 13 closes and air is removed from the main air pipe 6. The inflow of high pressure air stops. At the same time, the powder in the blow tank 1 is pushed out to the transport pipe 3 by pressure. This causes a loss in the pressure inside the blow tank 1, but the high pressure air supplied from the bypass pipe 15 compensates for this loss, so the internal pressure of the blow tank 1 is always maintained at a steady transport pressure, and as a result, The powder and granular material is continuously sent to the three portions of the transport pipe in fixed quantities.

The second embodiment also does not use an electrical control mechanism for supplying high-pressure air, has a simple configuration, and can further shorten pump-up time.

[Brief explanation of the drawing]

FIG. 1 is a front view of essential parts showing an embodiment of the present invention;
FIG. 2 is a front view of main parts showing another embodiment. 1... Blow tank, 3... Transport pipe, 6... Main air pipe, 7... High pressure air source, 9... Additional air pipe,
13...Pressure reducing valve, 15...Bypass pipe, 16...
Flow rate adjustment valve.

Claims (1)

[Scope of utility model registration request] A blow tank 1 that accommodates powder and granules, a transport pipe 3 connected to the bottom of the blow tank 1, a main air pipe 6 that communicates the blow tank 1 with a high-pressure air source 7, and a main air pipe 6. and an additional air pipe 9 which branches off from the main air pipe 9 and connects to the transport pipe 3, in which the main air pipe 6 is located downstream of the branch point with the additional air pipe 9 and is depressurized. valve 13
A pneumatic transportation device for powder and granular materials, characterized in that it is equipped with a.