JPH0326429Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a measuring device for powder and granular materials, and more particularly, to a measuring device for powder and granular materials that can measure a fixed amount of powder and granular materials, such as synthetic resin, transported by air in a measuring tank. .

In general, in order to transport powder and granular materials made of different materials stored in multiple storage tanks, and to meter them in fixed amounts and supply them to a mixing device, etc., a rotary feeder or the like is used from the storage tanks to a pneumatic transportation device. The powder is supplied to a transport tank, and an air pump installed in the transport transports the powder and granules from the transport tank to a weighing hopper of a weighing device, and after being weighed by the weighing device, it is transferred to a mixing device installed below the weighing hopper. It was made to supply.

However, in such conventional devices, the fixed quantity supply to the weighing device involves pneumatically transporting the powder or granules to the weighing hopper using the pneumatic transport device, and when the weighing device detects a predetermined weight, the transport device Even after the transport device is stopped, a large amount of powder or granules remaining in the pneumatic transport pipe interposed between the pneumatic transport device and the weighing device may enter the weighing hopper. Otherwise, a large amount of powder remains in the transport pipe, which inevitably causes variations in the supply of powder and granules to the weighing hopper, resulting in poor measurement accuracy.

Therefore, the present invention was devised in view of the above-mentioned circumstances, and its purpose is to provide a metering adjustment tank to be installed in the transportation system by means of pneumatic transport of powder and granules, and to transport the powder and granules in a small amount to compensate for the shortage in the pneumatic transportation. In combination with a metered supply device that feeds powder and granules in small amounts, there is no variation in the metered supply of powder and granules, and the measurement precision can be improved.

Therefore, the configuration of the present invention is such that a measuring tank is provided with a measuring device, and the granular material is pneumatically transported to the tank, while a metric adjustment tank is provided in the pneumatic transportation system for the granular material, and the measuring device is installed in the measuring tank. A quantitative supply device is provided between the adjustment tank and the measuring tank.

Embodiments of the measuring device of the present invention will be described below based on the drawings.

1 is a measuring/mixing tank for powder and granules, and a filter 1 is installed above the tank to separate air and powder.
1 and a supply port 12, and a discharge port 13 is provided at the bottom, and a pneumatic transportation device 2 for powder and granular material is provided at the supply port 12.
An air transport pipe 21 communicating with the transport tank 20 is connected, and an air pump 22 provided in the transport tank 20 is used to transport air from the transport tank 20 to the tank 1, while a discharge damper 13a is connected to the discharge port 13. It is set up.

Further, a mixing blade 14 is rotatably supported inside the tank 1, and the mixing blade 14 is attached to the tank 1.
It is intended to be driven by a motor 3 provided at the bottom of the.

The tank 1 is supported by a base 4 so as to be movable up and down, and a measuring device 5 such as a load cell is provided between the tank 1 and the base 4. This weighing device 5 detects the weight of powder and granules supplied to the tank 1 just before a predetermined amount, for example, when 90% to 95% of the predetermined amount is supplied, and outputs a primary detection signal electrically. The system detects the weight when 100% is supplied and sends a secondary detection signal that is electrically output.

The tank 1 is movable up and down with respect to the base 4,
In addition, as a means for measuring, a through hole 41 is provided in the center of the base 4, and the motor 3 provided at the lower part of the tank 1 can be inserted into the through hole 41. A plurality of support tubes 15 are provided at the lower part of the outer periphery, and the support tubes 15 are opened at the bottom, and air cylinders 4 are installed at locations corresponding to the support tubes 15 on the base 4.
2..., these air cylinders 42... are inserted into the support tube 15... via the measuring device 5, and the tank 1 is moved above the base 4 by the expansion of these air cylinders 42... The tank 1 is lifted to enable measurement by the measuring device 5, and the tank 1 is placed on the base 4 via the support tubes 15 by shortening each air cylinder 42.

Reference numeral 6 denotes a metering adjustment tank provided in the middle of the air transport pipe 21. As shown in FIG. A quantitative supply device 61 for supplying a fixed amount according to the rotational speed of Euphida etc. is provided, and the supply device 61 and the tank 1 communicate with each other via a communication pipe 62 equipped with an on-off valve 63. Accordingly, the powder and granular material that is insufficient during the pneumatic transportation is supplied from the metering adjustment tank 6 to the tank 1.

7 is a storage tank disposed above the transport tank 20 via a rotary feeder 71, and 8 is a discharge pipe connected to the discharge port 13.

Also, this discharge pipe 8, air transport pipe 21 and communication pipe 6
2, a flexible tube is used at least near the tank 1 so as not to affect the measurement by the measuring device.

The weighing device of the present invention is constructed as described above, and in order to weigh a fixed amount of powder and granular material stored in the storage tank 7 and supply it to the weighing/mixing tank 1, first, from the storage tank 7 to the rotary feeder. 71 to the transport tank 20, and then the inside of the transport tank 20 is pressurized by the air pump 22, and the powder and granules accommodated in the transport tank 20 are transferred to the air transport pipe 21.
and transported to the tank 1 via. At the time of this transportation, powder and granules also accumulate in the metering adjustment tank 6 provided in the middle of the transport pipe 21. When the amount of powder and granular material supplied to the tank 1 due to the transportation reaches 90% to 95% of the predetermined supply amount, the measuring device 5 detects this and the primary Controller (not shown) by detection signal
The air pump 22 is stopped by an output signal output from the tank 1, and the powder and granular material is supplied to the tank 1 so that the amount of powder and granular material supplied is less than a predetermined supply amount.

Thereafter, the opening/closing valve 63 is opened and the fixed quantity supply device 61 is driven to transfer the powder and granules accumulated in the metering adjustment tank 6 provided in the middle of the air transport pipe 21 to the tank 6.
When the supply of powder and granules to the tank 1 reaches a predetermined supply amount, the measuring device 5 detects this, and the metering device 5 detects this. The on-off valve 63 is closed by the output signal outputted from the controller in response to the secondary detection signal, and the quantitative supply device 61 is stopped. Since the powder and granular material is supplied to the measuring/mixing tank 1 by the combination of the pneumatic conveying device 2 and the metering supply device 61 in this way, there is little variation in the supply of the powder and granular material, and measurement accuracy can be improved. be.

Next, the air cylinders 42... are shortened, and
The tank 1 is placed on the base 4 via the support cylinder 15, and the motor is started to rotate the mixing blades 14 to mix the powder and granular material in the tank 1 for a certain period of time, and then the mixture is finished. is detected mainly by a timer, the discharge damper 13a is opened while the mixing blade 14 is kept rotating, and the mixed powder is passed from the discharge port 13 through the discharge pipe 8 to a storage hopper of an extrusion molding machine, for example. It is discharged to other places.

After such discharge, the motor 3 is stopped and the discharge damper 13a is closed by an output signal output from the controller by the operation of a sensor that detects the completion of discharge.

In the above embodiments, a pressurized air pump 22 was used as the air transport means, but a vacuum pump may be used instead of the pump 22.

In this case, the vacuum pump is preferably attached to the upper part of the tank 1 via a back filter.

In addition, if a measuring device and a mixing device are provided in one tank as in the embodiment, it is possible to quantitatively measure and mix powder and granular materials in one tank, which makes it possible to use a conventional weighing hopper. By omitting this, the entire equipment for transporting, measuring, and mixing powder and granular materials can be downsized and provided at low cost.

As described above, the present invention provides a metering device in a metering tank, and pneumatically transports powder and granules to the tank, and also provides a metering adjustment tank in the pneumatic transportation system for the powder and granules. Since a metering supply device is provided between the metering tank and the measuring tank, after the powder and granules are transported by pneumatic transportation to just short of the predetermined amount, the amount of powder and granules that are insufficient due to the pneumatic transportation is The powder can be supplied in minute amounts from a metering adjustment tank provided in the pneumatic transportation system of the powder and granules using a metering supply device, thereby reducing variations in supply of the powder and granules and improving measurement accuracy.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view showing an embodiment of the mixing device of the present invention, and FIG. 2 is a sectional view taken along the line -2 of the measuring tank. 1...Measuring tank (measuring and mixing tank), 14
... Mixing blade, 5 ... Metering device, 6 ... Metering adjustment tank, 61 ... Constant supply device.

Claims (1)

[Scope of utility model registration request] A metering device is provided in the metering tank, and the powder and granules are pneumatically transported to the tank, and a metering adjustment tank is provided in the pneumatic transportation system for the powder and granules, and a metering device is provided between the metering tank and the metering tank. A measuring device for powder and granular material, characterized in that a metering device is provided in the metering device.