RU2485450C1 - Weight batcher of discrete action for powdery materials - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: weight batcher of discrete action for powdery materials comprises a feeder, a control unit, and also a weight-receiving hopper installed on a weight metre and comprising an auger unloading device with an electric drive. At the same time, according to the invention, the feeder is equipped with a gate with a pneumatic drive, the auger unloading device is equipped with a valve with a pneumatic drive, and the weight metre is a platform strain gauge balance.

EFFECT: higher accuracy and stability of batching of powdery materials with different flowability.

1 dwg

Description

The invention relates to techniques for weighted discrete dosing of powdered materials. It can find application in various industries where it is necessary to dose various powder materials.

Known weighted discrete action dispensers of the DPD type (Orlov S.P. Dosing devices. - M.: Mashinostroenie, 1966, pp. 89-95), as well as the Gamma 50 dispenser of the Tenzo-M company located near Moscow (Tenzo catalog -M ”for 2005, p.18-19).

The disadvantage of this type of dispenser is that the dose is formed when the powder is collected in the load receptor (bucket, hopper). After a set dose has been set, the cargo receiving device is emptied by opening the bottom of this device. In this case, the powder, under the influence of its weight, is poured into the subsequent technological apparatus or into the container during packaging. In this case, in the case of dispensing powders, a certain portion of the powder adhering to the walls and the bottom remains in the load receptor. When working with poorly flowing powders, the mass of adhering powder can be up to 20% of the dose, in the case of working with well-flowing powders, up to 5%. In part, this process can be taken into account by using automatic correction of the task for a set of each subsequent dose. This gives an effect when the sticking is a more or less stable value over a large number of dosing cycles. Otherwise, any change in the amount of sticking within one cycle affects the value of the dose issued in this cycle.

Known dispenser of small additives of the company "Tenzo-M" (Catalog of the company "Tenzo-M" for 2005, p.26-27). This dispenser is taken as a prototype.

It is intended for dispensing poorly loose products such as milk powder, flour and other powder products that are similar in properties. In this dispenser, the problem of powder sticking to the load hopper is removed due to the fact that the dose from it is issued by a special unloading device - a vertical screw. At the same time, after delivery of the dose, a guaranteed non-discharged residue remains in the hopper, which excludes the influence of adhering powder on the dose. The dispenser includes a feeder designed to replenish the weighing hopper of the dispenser with a product. The load hopper contains a vertical auger with a drive. The hopper, together with the auger and the drive, is suspended on several strain gauge sensors, with the help of which the product is fed into the hopper and the product is discharged from the hopper. The dispenser includes a control unit.

The disadvantages of the dispenser adopted for the prototype. The dispenser is not suitable for dispensing powders with medium and good flowability, since the vertical screw cannot serve as a shut-off device at the outlet of the powder from the hopper at the end of the dispensing. Powder with good flowability practically without obstacles flows out of the hopper through the gap between the screw flanges and the hopper outlet sleeve, and also through the screw cavity of the screw inter-turn space.

The screw feeder in the prototype also has a drawback. From experience with such feeders, it is known that when the screw stops, some more powder is poured from the feeder trough. Such pouring of powder into the load hopper can continue during the dose from the hopper and disrupt the formation of the issued doses, i.e. uncontrollably increase the dosing error.

The technical task of the invention is to ensure the stable operation of a discrete-weight weighing batcher on powders with different flowability and increasing the dosage accuracy.

The technical result is achieved due to the fact that the discrete weighing batcher consists of a feeder, a load hopper mounted on a weight meter and containing an electric screw conveyor, as well as a control unit. At the same time, the feeder is equipped with a pneumatic damper, the screw discharge device is equipped with a pneumatic actuator, and platform tensometric scales are used as a weight meter.

The invention is illustrated in the drawing, which schematically depicts a weighing discrete discrete action for powder materials.

1 - platform strain gauge scales;

2 - load receiving hopper;

3, 5 - electric drive;

4 - control unit;

6, 11 - pneumatic drive;

7 - feeder;

8 - shutter;

9 - auger unloading device;

10 - valve.

The discrete weighing batcher for powdered materials consists of a feeder 7 and a load hopper 2 mounted on a platform strain gauge 1. The feeder 7 is equipped with a shutter 8 with a pneumatic actuator 6. The load hopper 2 includes a screw discharge device 9 with an electric drive 3. At the exit of the screw discharge a valve 10 with a pneumatic actuator 11 is installed. Proportional to the load, an electric signal from a platform strain gauge balance is transmitted to a control unit 4, which is implemented algorithm of the dispenser. Feeder 7 is designed to replenish powder in the hopper 2. The requirements for the amount of powder loaded into the hopper are limited only by the fact that each load should provide a non-discharged residue in the hopper after the dose is delivered within 0.5-1.0 dose quantities. The feeder 7 may be an independent device and not be included in the design of the dispenser, but the electric drive 5 of the feeder must be controlled by signals from the control unit 4.

The dispenser works as follows. The pneumatic actuator 6 opens the shutter 8, turns on the electric actuator 5 of the feeder 7 (or an external feeder), approximately 1.5 doses of powder are loaded into the load hopper 2. This process is monitored by platform tensometric scales 1 and, upon reaching a predetermined mass of powder in the load hopper 2, the electric drive 5 of the feeder 7 is turned off and the shutter 8 is closed. The time delay for accurate weighing of the powder mass collected in the hopper 2 is given. Then, the valve 10 opens with the pneumatic cylinder 11, the electric drive 3 of the screw discharge device 9 is turned on, and the dose is dispensed to the subsequent technological device, for example, to the mixer. The dispensing process is controlled by platform tensometric scales 1 and, upon reaching the set dose weight, the electric actuator 3 turns off, the pneumatic actuator 11 closes the valve 10. After the dose is dispensed, the remaining powder is accurately weighed in the load hopper 2, the dose value is determined and displayed on the recording device of the control unit 4. Then the dosing cycle is repeated.

Introduction to the metering design of the shutter 8 at the output of the feeder 7, installation of the valve 10 at the output of the screw discharge device 9 will ensure stable operation of the metering unit both on powders with poor flowability and on well-flowing powders. This constructive solution allows to increase the accuracy of dosing compared to the prototype.

A pilot industrial sample of the proposed dispenser was tested under the conditions of production of the Federal State Unitary Enterprise “Research Institute of Polymer Materials” with positive results.

Claims (1)

Discrete weighing batcher for powder materials, consisting of a feeder, a control unit, a hopper mounted on a load cell and containing an electrically driven screw unloading device, characterized in that the feeder is equipped with a pneumatically operated shutter, the screw discharge device is equipped with a pneumatic valve, and as We used platform tensometric scales.