WO2016139679A1

WO2016139679A1 - System and method for calculating grain fineness

Info

Publication number: WO2016139679A1
Application number: PCT/IN2016/000059
Authority: WO
Inventors: Pushkraj Janwadkar
Original assignee: Pushkraj Janwadkar
Priority date: 2015-03-04
Filing date: 2016-03-03
Publication date: 2016-09-09

Abstract

A weighing apparatus includes a weighing platform, a controller, a sensor, a memory, a display unit, and a transfer port. A predetermined weight of each sieve is stored in the memory. A weight of each sieve having a portion of granular material is determined individually by the sensor The controller calculates a difference weight between the predetermined weight of each sieve and the weight of each sieve having a portion of a granular material. The controller further calculates a grain fineness number of the granular material.

Description

System and method for calculating grain fineness

BACKGROUND

FIELD OF INVENTION

The present invention relates to a system and a method to automatically calculate weight of a granular material. More specifically, the present invention relates to an apparatus and a method to automatically calculate a grain fineness number (GFN) of the granular material.

BACKGROUND OF THE INVENTION

Size and composition are important factors to determine quality of a granular material. Granular materials with different sizes have different mechanical and chemical properties. Traditionally, particle size analysis or sieve analysis or sieving process is used for particle sizing in which lager particles are separated from fine particles. The process incorporates sieves of different mesh sizes and a vibration mechanism. The sieves are arranged one above the other in a vertical manner. Sieve with largest mesh size is placed at top and sieve with smallest mesh size is placed at bottom. The mesh size of each sieve decreases from top to bottom in the order. At base of this arrangement, a collector plate is positioned to collect finest particles. To begin the process, the sieves are placed over the vibration mechanism and topmost sieve receives the granular material. The vibration mechanism vibrates the arrangement so that the finest particles travel to the collector plate. Each sieve may retain a particular quantity of the granular material on it which is weighted further.

To determine weight of the granular material retained on each sieve, the granular material has to be transferred to a weighing pan by cleaning the sieve. To begin with, the weighing pan is placed over a weighing machine and its weight is noted as a reading. Thus, the weight of the weighing pan without the granular material is determined. Further, the weight of the weighing pan with the granular material is determined by the weighing pan. The weight of the granular material retained on each sieve is determined by subtracting the ϊ weight of the weighing pan with the gianular material from the weight of the weighing pan without the granular material. Here, calculation of weight of the granular material is a manual process. Subsequently, a grain fineness number (GFN) of the granular material is determined using a formula manually. Further, manual or automated cleaning of the sieve is a tedious task and is inefficient. Hence, readings might get affected when the sieve is not cleaned properly. Furthermore, taking down readings and performing manual calculations take lot of time and may lead to human errors.

U.S. Patent No. 5,222, 605 discloses an apparatus which automatically analyses particle size of a granular material. The apparatus comprises a conveyor system, sieves arrangement which is cantilevered to the conveyor system, a pan at bottom of the sieves arrangement, a weighing apparatus, and an automatic sieve cleaner. The conveyor system has a vertical movement and is also movable around a horizontal roll at bottom of said vertical movement. Sieves are arranged in a vertical manner one over the other and are connected to the conveyor system individually. The sample to be analysed is introduced onto the topmost sieve and the entire arrangement is vibrated. This separates the larger granular particles from the finer particles and the granular particles of various sizes are retained on the respective sieves. The pan collects and holds the finest particles of the granular material that has fallen through all the other sieves. The conveyor system moves each sieve from its arrangement and dumps particles retaining on sieve by inverting the sieve onto the weighing apparatus. The automatic sieve cleaner includes a brush mechanism individually that cleans the sieve while it is in inverted position. The weighing apparatus sequentially records the weight of the particles. Further, weight percentage proportions of the respective particles on the sieves are calculated.

The patent described above includes complex and heavy machineries. This makes the apparatus costly and bulky. Moreover, the apparatus require a larger space to setup and is not portable. Further, the cleaning apparatus is not reliable because some fine particles may remain in the sieve which can affect the final result.

In light of the foregoing discussion, there is a need for an apparatus that automatically calculates the weight of the granular material and the grain fineness number without any manual calculations. Moreover, there is need for a system that prevents loss of particles due to inefficiency in cleaning the sieve. OBJECTS OF THE INVENTION

An object of the present invention is to store predetermined weight of sieves in a weighing apparatus. The predetermined weight of each sieve is obtained by the weighing apparatus. Sieves that contain no granular material i.e. empty and clean sieves are placed on the weighing platform one at a time to obtain the predetermined weight of each sieve and collector pan. Another object of the present invention is to store weight of each sieve at the end of sieving process. Each sieve includes a unique mesh size and may retain some amount of granular material as per the mesh size of the sieves. Post sieving, the sieves are placed on the weighing platform one at a time to obtain weight of each sieve and the collector pan. Yet another object of the present invention is to calculate a difference weight and a grain fineness number (also known as AFS number or specific surface reading) of the granular material. The difference weight and the grain fineness number are displayed on a display unit and are stored in a memory as data. The data can be transmitted to any electronic device such as computer and laptop.

SUMMARY

The present invention overcomes shortcomings of the prior art particle size analyser systems. A weighing apparatus disclosed herein includes a weighing platform, a controller, a sensor, a memory, and a display unit. The weighing apparatus stores a predetermined weight of a sieve. The sieve that contains a first quantity of the granular material is placed on the weighing platform. The sensor is connected to the weighing platform to measure a first weight of the first sieve that contains the first quantity of the granular material. The weighing apparatus calculates difference weight and a grain fineness number. A controller is connected to the sensor and the memory to receive the weight and the predetermined weight, respectively. The controller calculates a difference weight i.e., weight of the granular material retained on the sieve between the weight and the predetermined weight. The controller further calculates a grain fineness number (GFN) of the granular material based on the difference weight. A display unit to display the difference weight and the grain fineness number of the granular material.

According to an embodiment of the present invention, the weighing apparatus avoids manual calculations to determine the weight of granular material and determine grain fineness number of the granular material. This prevents the risk of manual errors and provides an efficient grain fineness calculator.

BRIEF D I SCRIPT ION OF DRAWINGS

The invention is described in detail below with reference to the drawings and examples. Such discussion is for purposes of illustration only. Modifications within the spirit and scope of the present invention, set forth in the appended claims, will be readily apparent to one of skill in the art. Terminology used throughout the specification and claims herein is given its ordinary meaning except as more specifically defined:

Fig. 1 A is a schematic representation of a weighing apparatus;

Fig. IB is a schematic representation of the weighing apparatus, where a sieve is placed on a weighing platform;

Fig. 1C is a schematic representation of the weighing apparatus, in accordance with an embodiment of present invention; and Fig. 2 is a flow chart illustrating the method for calculating grain fineness number.

DETAIL DISCRIP )F EMBODIMENTS

As used in the specification and claims, the singular forms "a", "an" and "the" include plural references unless the context clearly dictates otherwise. For example, the term "an article" may include a plurality of articles unless the context clearly dictates otherwise. Those with ordinary skill in the art will appreciate that the elements in the Figures are illustrated for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the Figures may be exaggerated, relative to other elements, in order to improve the understanding of the present invention.

There may be additional components described in the toregoing application that are not depicted on one of the described drawings. In the event such a component is described, but not depicted in a drawing, the absence of such a drawing should not be considered as an omission of such design from the specification.

Before describing the present invention in detail, it should be observed that the present invention utilizes a combination of system components which constitutes a weighing apparatus for granular material. Accordingly, the components and the method steps have been represented, showing only specific details that are pertinent for an understanding of the present invention so as not to obscure the disclosure with details that will be readily apparent to those with ordinary skill in the art having the benefit of the description herein.

As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting but rather to provide an understandable description of the invention.

A schematic representation of the weighing apparatus 100 for granular material is shown in Fig.lA. The weighing apparatus 100 includes a weighing platform 102, a controller or computer (not shown), a memory (not shown), a sensor (not shown), a display unit or monitor or screen 104, a number pad or keyboard 106, and a data transfer port 108. The weighing apparatus 100 is used to calculate a grain fineness number (GFN) of the granular material. The granular material is sieved using a sieving machine. The sieving machine (not shown) which is used for sieve analysis has a set of sieves. The sieve analysis is performed to determine distribution of the coarse soil, and variety of powders and granulated materials. The sieving machine typically has a vibration mechanism which vibrates the set of sieves. The set of sieves are assembled in ascending order from top according to their mesh sizes. A topmost sieve has largest mesh size and bottommost sieve has smallest mesh size A collection pan is placed at bottom of the bottommost sieve to collect fine particles of the granular material. Prior to sieving, each sieve of the set of sieves is placed over the weighing platform 102 in a sequential order. For illustrative purposes, the weighing apparatus 100 with a sieve 110 placed on the weighing platform 102 is shown in the FIG. IB. In the sequential order, the topmost sieve is placed initially on the weighing platform 102 followed by remaining sieves and the bottommost sieve or vice a versa. A user can place only a single sieve at a point of time on the weighing platform 102. When the topmost sieve is removed from the weighing platform 102, the user can place the next sieve over the weighing platform 102. The sensor connected to the weighing platform 102 determines weight of each sieve. The weight of each sieve prior to sieving is stored as a predetermined weight in the memory. The predetermined weight of each sieve is stored in the memory. The predetermined weight of each sieve is measured prior to sieving i.e., pre sieving. A granular material is poured on the topmost sieve and the vibration mechanism vibrates the set of sieves. The granular material may be at least one of sand, crushed rock, clay, granite, feldspar, coal, soil, manufactured powder, grain, seeds or powdered or granulated materials. When the set of sieves are vibrated or undergoes sieving process, the granular material passes through each sieve and each sieve may retain a quantity of the granular material on it. Further, post sieving each sieve with the quantity of the granular material is placed on the weighing platform 102 in the sequential order. The sensor connected to the weighing platform 102 determines weight of each sieve containing a quantity of the granular material. The weight of each sieve is measured post-sieving. The weight of each sieve that contains the quantity of the granular material is stored in the memory.

The controller is connected to both the memory and the sensor The controller retrieves stored data from the memory and calculates a difference weight for each sieve. The difference weight is the difference between the weight of each sieve containing the quantity of the granular material and the predetermined weight of the each sieve. In other words, the difference weight is a weight of quantity of the granular material retained in each sieve. The display unit 104 displays the difference weight of each sieve. Similarly, difference weights for other sieves are determined and stored in the memory. The controller further retrieves data from the memory and calculates the grain fineness number (GFN) based on the determined difference weights. The grain fineness number (GFN) is a mathematical formula stored in the memory. The display unit 104 displays the grain fineness number (GFN) of the granular material.

When another granular material is used for sieving analysis with the same set of sieves, predetermined weights corresponding to the set of sieves remain same. Moreover, the controller uses the stored predetermined weights to calculate the grain fineness number (GFN). The grain fineness number is also referred as AFS number (typically in Foundry Industry) or specific surface reading. When a new set of sieves are used, the weighing apparatus 100 allows the user to overwrite the existing predetermined weights with new set of predetermined weight values. In an embodiment, predetermined weights of the new set of sieves can be stored in the memory without overwriting the predetermined weights of previous set of sieves, thereby allowing the user to select predetermined weight of any sieve.

As shown in Fig. 1A, the weighing platform 102 is positioned over a small vertical bar 103 of the weighing apparatus 100. In an embodiment, top portion of the weighing apparatus 100 may be the weighing platform 102 as shown in Fig. 1C. The controller may be, but not limited to a microcontroller, a microprocessor with appropriate circuitry, or a programmable logic controller (PLC) or a Computer. The controller is programed to retrieve the stored mathematical formula from the memory to calculate the grain fineness number (GFN) of the granular material. The sensor may be a load sensor or a weight sensor. The display unit 104 may be at least one of, but not limited to a LED display, a LCD display and an eight segment display. All the stored results are displayed on the display unit 104. Further, the stored results are transmitted between a computer or a laptop or a mobile or a PDA and the weighing apparatus 100 through the data transfer port 108. In an embodiment, the number pad 106 allows a user to enter weight of each sieve. The entered weight is stored in the memory as a predetermined weight of each sieve.

In an embodiment, the set of sieves are first, second, third, fourth, and fifth sieves. The first sieve has a largest mesh size and the fifth sieve has a smallest mesh size. A collection pan is placed at bottom of the fifth sieve to collect fine particles of the granular material. Prior to sieving, the first sieve is placed over the weighing platform 102. The sensor connected to the weighing platform 102 determines weight of the first sieve. The weight of the first sieve is stored as a first predetermined weight in the memory. The display unit 104 displays the first predetermined weight of the first sieve. The first, second, third, fourth, and fifth sieves are placed over the weighing platform 102 in the sequential order. Here, the sequential order is according to mesh sizes of first, second, third, fourth, and fifth sieves. Initially, the first sieve is placed over the weighing platform 102 followed by the second, third, fourth, and fifth sieves. The second sieve is placed over the weighing platform 102 only when the first sieve is removed from the weighing platform 102. The sensor connected to the weighing platform 102 determines weight of the second sieve. The weight of the second sieve is stored as a second predetermined weight in the memory. Similarly, weights of the third, fourth, and fifth sieves are determined by the sensor and are stored as third, fourth, and fifth predetermined weights, respectively in the memory.

When the vibration mechanism vibrates or set of sieves undergo sieving process, the first, second, third, fourth, and fifth sieves vibrate and the granular material poured on the first sieve passes through each of them and reaches the pan. Each of the first, second, third, fourth, and fifth sieves may retain some quantity of the granular material. The first sieve containing a first quantity of the granular material is placed on the weighing platform 102. The sensor connected to the weighing platform 102 determines weight of the first sieve containing the first quantity of the granular material. A first weight is the weight of the first sieve containing the first quantity of the granular material post sieving. The first weight is stored in the memory. The controller retrieves stored data from the memory and calculates a first difference weight for the first sieve. The first difference weight is the difference between the first weight and the first predetermined weight. The display unit 104 displays the first difference weight of the first sieve. Similarly, second, third, fourth, and fifth difference weights of the second, third, fourth, and fifth sieves, respectively are calculated by the controller and stored in the memory. The controller retrieves stored data from the memory and calculates a grain fineness number (GFN) based on the determined first, second, third, fourth and fifth difference weights. The display unit 104 displays the grain fineness number (GFN) of the granular material. Although the disclosed weighing apparatus 100 illustrates usage of five sieves, for a person who is skilled in the art it is well evident that the disclosed apparatus is not limited to usage of the five sieves. A flowchart in Fig. 2 illustrates a method to calculate a grain fineness number for the granular material. At step 202, first and second predetermined weights of first and second sieves are stored in the memory. The first and second predetermined weights are determined individually with help of sensor and are stored in the memory. At step 204, first and second weights of the first and second sieves are determined individually. The first and second weights of the first and second sieves are weights of the first sieve containing first quantity of the granular material and the second sieve containing second quantity of the granular material, respectively. At step 206, the controller calculates first and second difference weights of the first and second sieves, respectively. The first difference weight is the difference between the first weight and first predetermined weight. The second difference weight is the difference between the second weight and second predetermined weight. At step 208, the controller further calculates the grain fineness number of the granular material based on the first and second difference weights. The grain fineness number is calculated using a mathematical formula. The grain fineness number is stored in the memory. At step 210, the display unit 104 displays the first and second difference weights and the grain fineness number.

For example, prior to sieving process, weights of the first and second sieves are determined using the sensor connected to the weighing platform 102. The weights of the first and second sieves are 50 grams and 60 grams, respectively. The weights of the first and second sieves are stored as first and second predetermined weights, respectively in the memory. Post sieving, the first and second weights of the first and second sieves, respectively are determined using the sensor connected to the weighing platform 102. The first and second sieves retain first and second quantities of a granular material. The first and second weights of the first and second sieves are 450 grams and 400 grams, respectively. The first and second weights are stored in the memory. The controller retrieves the stored data and calculates first and second difference weights. The first and second difference weights are the first and second quantities of the granular material retained on the first and second sieves, respectively.

The first difference weight = first weight - first predetermined weights = 450 grams - 50 grams = 400 grams The second difference weight = second weight - second predetermined weights = 400 grams - 60 grams = 340 grams

A grain fineness number is a mathematical formula which is pre-stored in the memory. The mathematical formula uses the first and second difference weights as parameters. The controller retrieves the mathematical formula from the memory and calculates the grain fineness number of the granular material.

The weighing apparatus 100 is a portable and efficient system which is capable of calculating weight of granular material retaining on each sieve. Further the weighing apparatus 100 is used to calculate the grain fineness number of the granular material simultaneously. The weighing apparatus 100 avoids manual calculations to determine the weight of granular material and grain fineness number of the granular material. This prevents the risk of manual errors. Further, the weighing apparatus 100 saves the hassle of cleaning sieves after sieving process to obtain the sample of granular material which needs to be weighted. Further, the weighing apparatus 100 prevents the loss of sample due to inefficiency in cleaning of sieve. Moreover, the weighing apparatus 100 prevents loss of results which are obtained as it transfers all results to a computer. The weighing apparatus 100 has simpler arrangement as compared to the particle size analyser of prior art, it is easy to manufacture, and is cost-effective.

The present invention has been described herein with reference to a particular embodiment for a particular application. Although selected embodiments have been illustrated and described in detail, it may be understood that various substitutions and alterations are possible. Those having ordinary skill in the art and access to the present teachings may recognize additional various substitutions and alterations are also possible without departing from the spirit and scope of the present invention, and as defined by the following claims.

Claims

What is claimed is:

1 . A weighing apparatus for a granular material, comprising: a memory to store a first predetermined weight of a first sieve; a weighing platform, wherein the first sieve that contains a first quantity of the granular material is placed on the weighing platform, a sensor connected to the weighing platform to measure a first weight of the first sieve that contains the first quantity of the granular material; a controller connected to the sensor and the memory to receive the first weight and the first predetermined weight, respectively, and calculate a first difference weight between the first weight and the first predetermined weight and a grain fineness number (GFN) of the granular material based on the first difference weight; and a display unit to display the first difference weight and the grain fineness number (GFN) of the granular material.

2. The weighing apparatus of claim 1, wherein the memory stores a second predetermined weight of a second sieve.

3. The weighing apparatus of claim 2, wherein the second sieve that contains a second quantity of the granular material is placed on the weighing platform, and wherein the sensor measures a second weight of the second sieve that contains the second quantity of the granular material.

4. The weighing apparatus of claim 3, wherein the controller calculates a second difference weight between the second weight and the second predetermined weight.

5. The weighing apparatus of claim 4, wherein the controller calculates the grain fineness number (GFN) based on the first and second difference weights.

6. The weighing apparatus of claim 3, wherein the first and second quantities of the granular material have first and second particle sizes, respectively.

7. The weighing apparatus of claim 3, the sensor measures the first and second predetermined weights.

8. The weighing apparatus of claim 3 further comprising a number pad, wherein the first and second predetermined weights are entered through the number pad.

9. The weighing apparatus of claim 1 further comprising a port to allow data transfer between the controller and at least one of a computer, a laptop, a mobile, and a personal digital assist (PDA).

10. The weighing apparatus of claim 1, wherein the granular material may be at least one of sand, crushed rock, clay, granite, feldspar, coal, soil, manufactured powder, grain, seeds or other powdered or granulated materials.

11. A weighing apparatus for a granular material, comprising: a memory to store first and second predetermined weights of first and second sieves, respectively, wherein the first and second sieves contain first and second quantities of the granular material; a weighing platform, wherein the first and second sieves are individually placed on the weighing platform, and wherein the second sieve is placed on the weighing platform subsequent to a removal of the first sieve from the weighing platform; a sensor connected to the weighing platform to measure first and second weights of the first and second sieves that contain the first and second quantities of the granular material, respectively; a controller connected to the sensor and the memory to receive the first and second weights, and the first and second predetermined weights of the first and second sieves, respectively, and calculates a first difference weight between the first weight and the first predetermined weight, a second difference weight between the second weight and the second predetermined weight and a grain fineness number (GFN) of the granular material based on the first and second difference weights; and a display unit to display the first and second difference weights and the grain fineness number (GFN) of the granular material.

12. The weighing apparatus of claim 11 further comprising a number pad, wherein the first and second predetermined weights are entered through the number pad.

13. The weighing apparatus of claim 11 further comprises a port to allow data transfer between the controller and at least one of a computer, a laptop, a mobile, and a personal digital assist (PDA).

14. The weighing apparatus of claim 11, wherein the granular material may be at least one of sand, crushed rock, clay, granite, feldspar, coal, soil, manufactured powder, grain, seeds or powdered or granulated materials.

15. A method for measuring a first weight of a granular material, comprising: storing a first predetermined weight of a first sieve; measuring the first weight of the first sieve that contains a first quantity of the granular material; calculating a first difference weight between the first weight and the first predetermined weight and a grain fineness number (GFN) of the granular material based on the first difference weight; and displaying the first difference weight and the grain fineness number (GFN) of the granular material.

16. The method of claim 15 further comprising allowing data transfer between the controller and at least one of a computer, a laptop, a mobile, and a personal digital assist (PDA) by way of a port.