JPS638417Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a mixing device for powder and granular materials, and more particularly, to a mixing device for mixing powder and granular materials in a mixing tank equipped with mixing blades.

In general, powder and granules made of different materials stored in a plurality of storage tanks are supplied in fixed amounts to a mixing device for mixing, and the mixed powder and granules are transported from the mixing tanks. The powder is supplied to a mixing tank through a metering device and a metering device such as a screw feeder, a rotary leaf feeder, or a table feeder, and a transport tank is provided below the tank, and the powder mixed by the mixing device is supplied to the mixing tank. The powder was discharged from the mixing tank to the transport tank of the pneumatic transport device, and the powder was pneumatically transported from the tank via the pneumatic transport pipe by an air pump.

However, in such conventional systems, separate tanks are provided for each mixing device and pneumatic transport device, which not only requires large-scale equipment and high equipment costs, but also Since the devices need to be linked together and are assembled three-dimensionally in the vertical direction, there are problems such as requiring a large space for the equipment.

Therefore, the present applicant first provided an air transport pipe at the outlet of the mixing tank, and in conjunction with this air transport pipe, provided an air pump for pneumatically transporting the mixed powder and granules from the tank. proposed a method in which the mixed powder and granules were directly transported under high pressure by pneumatic transportation, but when the internal pressure of the tank increased, the powder and granules were connected to the rotating shaft of the mixing blade installed in the tank. The particles were blown out from the gap created between the rotary shaft and the through hole at the bottom of the tank, and there was a risk that the blown out powder and granules could have an adverse effect on the drive device and the like.

The present invention was devised in view of the above-mentioned problems.The purpose of the present invention is to enable the mixed powder and granular material to be conveyed under high pressure directly from the mixing tank by pneumatic conveyance, while the powder and granular material is transported directly from the mixing tank to the mixing tank. The air pressure inside the tank can be prevented from blowing out from the gap created between the rotating shaft of the mixing vane and the rotating shaft through hole of the tank.

Therefore, the configuration of the present invention is such that a supply damper and a discharge damper are provided at the supply port and the discharge port, respectively, and an air transport pipe is provided at the discharge port, and mixed powder and granules are transported in relation to the air transport pipe. An air pump is provided for transporting air from the tank, and a supply means is provided for supplying air at a higher pressure than the internal pressure of the tank into the tank from a gap between the rotating shaft and the through hole.

The mixing device of the present invention will be explained below based on the embodiments shown in the drawings.

Reference numeral 1 denotes a mixing tank for powder and granular material, which has a supply port 11 for the powder and granular material in its upper part, a discharge port 12 in its lower part, and a through hole 13 provided in the lower part of the tank 1. A drive device 2, such as a motor, in which a rotating shaft 21 of a mixing blade 20 is rotatably inserted into the tank 1, and this rotating shaft 21 is provided at the lower part of the tank 1.
It is designed to be driven by

Therefore, the present invention provides a supply damper 14 and a discharge damper 15 at the supply port 11 and discharge port 12, respectively, of the mixing device configured as described above, and also provides an air transport pipe 4 at the discharge port 12, and the air transport pipe In connection with 4, an air pump 5 for pneumatically transporting the mixed powder and granular material from the tank 1 is provided in the tank 1 via a communication pipe 51. A supply means 3 for supplying air at a pressure higher than the internal pressure of the tank 1 is provided in the tank 1.

As shown in FIG. 2, the supply means 3 uses a mounting member 30 having a through hole 31 in the center through which the rotating shaft 21 can be inserted, and a groove 32 continuous to the through hole 31. The motor 2 is fixed to the lower part of the mixing tank 1, and a sealed chamber A is formed between the upper surface of the motor 2 and the mounting member 30 by the groove 32, and the through hole 31 and the rotating shaft 21 are connected to each other. A sealing material 33 is provided between the two.

On the other hand, the communication pipe 51 is branched in the middle, and the branch pipe 52 is communicated with the sealed chamber A, and the pressure reducing valves 53 and 54 between the communication pipe 51 and the branch pipe 52 are
and opening/closing valves 55 and 56, and by adjusting these pressure reducing valves 53 and 54, the sealed chamber A
Air with a pressure higher than the internal pressure of the tank 1 is sent into the tank 1, and the air in the sealed chamber A is generated between the through hole 31 and the rotating shaft 21, that is, between the sealing material 33 and the rotating shaft 21. High pressure air is supplied into the tank 1 through the gap a.

Further, above the tank 1, hoppers 6, 6 for storing powder and granular materials of different materials are arranged as a pedestal 7, and below these hoppers 6, 6, a screw feeder or the like is quantified by the rotation speed. Feeding devices 61, 61 are provided, and a shutter 62 for guiding the powder to the supply port 11 of the tank 1 is provided below these feeding devices.

8 is a controller that has a built-in memory circuit, a comparison circuit, an arithmetic circuit, an output circuit, etc., and the controller 8 has a supply port and discharge dampers 14, 15.
The opening/closing devices 14a, 15a, the opening/closing devices for the pressure reducing valves 53, 54, the feeding devices 55, 56, and the driving/stopping devices for the motor 2 and the air pump 5 are connected, respectively.

The present invention is constructed as described above, and when the start switch of the controller 8 is turned on to mix and transport powder and granules made of different materials, the opening/closing device 14a is operated and the supply damper 14 is opened.
Furthermore, the feeding devices 61, 61 are driven to supply a fixed amount of powder and granules from each hopper 6, 6 to the tank 1 by rotation of the screw feeder.

Next, the supply damper 14 is closed by an output signal outputted from the controller 8, mainly from a timer, and the motor 2 is started to rotate the mixing blade 20 to mix the powder and granules in the tank 1 for a certain period of time. .

After the completion of this mixing is detected mainly by a timer or material thermometer, the on-off valves 55 and 56 are simultaneously activated by the output signal from the timer or material thermometer outputted from the controller 8 while the mixing blade 20 is kept rotating. The tank 1 is opened and high pressure air is sent from the air pump 5 to pressurize the inside of the tank 1.

At this time, if the pressure inside the tank 1 becomes high, the powder inside the tank 1 will be blown out from the gap a created between the rotating shaft 21 and the sealing material 33. The air pressure on the side of the branch pipe 52 provided in the middle of the communication pipe 51 is controlled by the pressure reducing valve 5.
3 and 54, the air pressure is set higher than the air pressure on the communication pipe 51 side, and the high-pressure air sent into the sealed chamber A from the branch pipe 52 is blown into the tank 1 through the gap a. This prevents the granular material in the tank 1 from blowing out to the outside, and prevents the granular material from entering the motor 2 or the like and causing an adverse effect.

When the internal pressure of the tank 1 reaches a predetermined pressure, the discharge damper 15 and the on-off valve 41 are opened to transport the mixed powder from the tank 1 through the air transport pipe 4 to a storage hopper of an extruder, for example. It is transported by air to other locations.

After such transportation, the motor 2 and the discharge damper 15 are activated by an output signal output from the controller 8 due to the operation of a sensor that detects the end of this transportation.
It will be closed down.

In addition, as in the embodiment, a branch pipe 52 is used as the supply means 3 to double as the air pump 5, and an air pump other than the air pump 5 is used, and the pump is equipped with a pressure reducing valve 54 and an opening/closing valve. valve 56
It is also possible to provide a communication pipe that communicates with the sealed chamber A.

As described above, the present invention provides a supply damper and a discharge damper at the supply port and the discharge port, respectively, and an air transport pipe is provided at the discharge port, and the mixed powder and granular material is transported in relation to the air transport pipe. An air pump for transporting air from the tank is provided, and a supply means is provided for supplying air at a pressure higher than the internal pressure of the tank from the gap between the rotating shaft and the through hole. The mixed powder and granules mixed in the mixing tank can be transported under high pressure directly from the tank by pneumatic transport, which eliminates the need to provide a separate transport tank for the pneumatic transport device in addition to the mixing tank for the mixing device. The entire device can be configured compactly, and can be installed at low cost in a narrow space.
Moreover, by supplying air with a pressure higher than the internal pressure of the tank into the tank through the gap between the rotating shaft and the through hole, the powder and granules in the tank are not blown out from the gap. It is possible to reliably prevent this, and it is also possible to prevent the powder and granular material from entering the drive device and the like and causing adverse effects.

[Brief explanation of the drawing]

The drawing shows an embodiment of the mixing device of the present invention.
FIG. 1 is a partially cutaway front view of the same, and FIG. 2 is an enlarged sectional view of the main part. 1... Mixing tank, 11... Supply port, 12...
Discharge port, 13... Through hole, 14... Supply damper, 15... Discharge damper, 2... Drive device, 2
0... Mixing blade, 21... Rotating shaft, 4... Air transport pipe, 5... Air pump, 3... Supply means, a...
…gap.

Claims (1)

[Scope of utility model registration request] A through hole is provided at the bottom of a mixing tank having a powder supply port at the top and a discharge port at the bottom, and a rotary shaft having a mixing blade is rotatably inserted into the through hole, and
A mixing device configured to drive this rotating shaft by a drive device provided at the bottom of the tank, wherein the supply port and the discharge port are provided with a supply damper and a discharge damper, respectively, and the discharge port is provided with an air transport pipe, In addition, an air pump is provided in connection with the air transport pipe to pneumatically transport the mixed powder and granules from the tank, while an air pump is provided in the tank through the gap between the rotating shaft and the through hole, which is lower than the internal pressure of the tank. A mixing device characterized by being provided with a supply means for supplying high-pressure air.