FR2587482A1 - Metering/weighing screw for pulverulent and granular products - Google Patents

Abstract

The invention relates to an apparatus allowing continuous metering and weighing of pulverulent and granular products. It consists of a receiving hopper A which receives the product to be treated. This hopper is connected to a barrel B in which there is placed a screw C which is driven by a d.c. motor. The unit is hinged around its centre of gravity and rests at D on a strain gauge. A remotely placed computer unit processes the weight and speed data transmitted by the gauge and motor, the assembly being driven by a control loop. This apparatus is intended for public works, industry, chemistry and farm production.

Description

 Apparatuses are known which combine the action of volumetric extractors associated with belt weighing systems making it possible to carry out continuous weight metering of pulverulent or granular products.

 The present invention relates to an apparatus for continuously distributing and weighing powdered or granular products by weight ensuring both functions.

 While the known systems require two successive operations, the good result of which is conditioned by perfect conditioning of the product to be treated, the invention presented makes it possible to remove these constraints since the product is entirely contained in a closed assembly ensuring the extrac - tion, distribution and dosage by weight.

I1 includes: (see drawing of the set) 5/5
I - An anti-clogging hopper (A), to condition the product, supplied either by natural flow, or by any means of mechanical continuous handling. An elastic suspension makes it possible to remove any constraint affecting the proper functioning. The hopper is fitted with control and packaging devices.

 II - A frame (B), forming a barrel, articulated on a chassis, the articulation being placed at the center of gravity of the vertical loads transmitted by the assembly.

 III - A screw shaft (C) fitted with turns ensuring proper filling and transport of the product to be treated to a distribution point. This screw shaft is driven by a variable speed motor.

 IV - A flow chain (D) which receives a weight information taken by a strain gauge and speed information from the drive motor. The whole is processed in a computer block, a regulation loop controlling everything.

The indexed drawings illustrate the whole
FIG. 1 represents the buffer hopper in which the material to be treated is supplied. The hopper is fitted with a 1/1 vibrator, a 1/2 mechanical or electrical level detection device, a 1/3 vent.

The assembly is mounted floating relative to the mechanical metering member and the framework. This arrangement makes it possible to more effectively transmit the effect of the vibrator ensuring better flow of the product.

 FIG. 2 represents the material receiving chamber where it is placed in compression in the articulation zone 2/1 placed at the center of gravity of the vertical forces.

 FIG. 3 represents a variant comprising the addition of a 3/1 rotor mechanically linked to the screw and ensuring good force-feeding.

 FIG. 4 represents an elevation view of the assembly which must necessarily work with an inclination.

 The process has many applications. It can be used in the dosing of powdered products and granular products used in Industry, Chemistry, Public Works, Food industry.

Claims (5)

 1) Device for carrying out distribution with weight dosage of powdery and granular products comprising:  A buffer hopper A  An articulated frame B  A screw C with feeding chamber  A flow chain D  2) Device according to claim 1, comprising the floating mounting of the buffer hopper A.  3) Device according to claim 1 ensuring the conditioning of the product in the booster chamber C1.  4) Device according to claims 1 - 2 - 3 providing for the recovery of vertical loads to the right of the joint.  5) Device according to claim 3 providing for the addition of the rotor E mark allowing the force-feeding.