Automatic control system of press compaction

Abstract

 It is especially applicable in the manufacture of tiles and pavement, obtaining these pieces upon compacting the granulate material (3) with a specific percentage of moisture, then followed by a drying, enameling, painting treatment, etc. and even kiln firing.
The automatic control of compaction takes place upon distributing pressure sensors (1) in the mold itself of the press, built in the top (2) or bottom (3) punch, whereby making it possible to obtain data when pressing takes place.
Therefore, the stability of the load is statistically controlled upon the sensors (1) communicating the force measured in differences of voltage, transforming these values into signals for a computer, by means of an amplifying system, processing these data to elaborate statistical values, etc., thus continuously informing about the pressing quality.
The load correction is done by means of the intelligent feed slide that feeds the press that receives the corresponding orders with the value packages obtained by statistical evaluation.

Description

OBJECT OF THE INVENTION

[0001] As is expressed in the title of this specification, the present invention refers to an automatic control system of press compaction, being especially applicable to the manufacture of tiles and pavements.

[0002] In the manufacture of ceramics, pieces are produced in dry presses, compacting a granulate material with a specific moisture, to thus attain solidly compacted pieces that endure, after being pressed, drying, enameling, painting, belt conveyance treatments, etc., even kiln firing, where they receive, by means of high temperatures, the definitive feature and resistance.

[0003] The homogeneity of the product with regard to correct compaction is very important for the physical resistance of the pieces during the drying and firing process and when a product contracts during firing, it is even more important, since any difference of compaction would cause contraction differences, in other words, deformed pieces would be produced.

[0004] The purpose of this invention is to attain an automatic control system of compaction and at the same time rapid, without the need of taking samples. With the data obtained continuously and automatically, very reliable and exact control of production can be achieved, since upon continuously having data after each pressing, statistically based decisions may be made, elaborating values based on many consecutive pressings, and in the event of adjustment by means of an intelligent feed slide, the load correction orders will also be considered on the grounds of many consecutive pressings and the possibility of mistakes upon processing non-representative values is eliminated.

BACKGROUND OF THE INVENTION

[0005] In the processes used up until now, in the one shown in patent 541.518 which claims a penetrometer to determine the density of the compacted ceramic piece, as well as the one developed by immersion in mercury in patent of invention P-8800227, both of the same applicant as of the present invention, the process is based on taking samples and therefore it is slow. No continuous control of production can be made and there is the risk that any sample taken does not represent true production, due to an instant load failure.

[0006] Patent of invention number P-8901208, also of the same applicant firm, refers to an intelligent feed slide to carry out the correction of load of ceramic material on the basis of a series of samples taken by hand.

DESCRIPTION OF THE INVENTION

[0007] The automatic control system of press compaction that is the object of the invention, makes it possible to obtain data about the compaction directly when pressing takes place by distribution of pressure sensors installed in the press mold itself.

[0008] In this way data of each pressing are obtained which makes it possible to control the load stability statistically. In other words, data of a single pressing (or sample) will not be taken for the evaluation of the load, but rather an entire series of pressings that may be few or many, depending on the load stability, in order to consider the load quality.

[0009] In order to carry out this control, pressure or force sensors, of the type used on the market, are installed in a mold punch, which may be a top or bottom punch.

[0010] When the compacting is done, when the top punch penetrates into the mold to compact the granulate material contained in it, the sensors measure the reactive force of the granulate material. Where there was a denser load, the compaction will logically be greater and the sensor in such an area will measure a higher force. Likewise, when it is an area with a smaller load, the compaction will be less and the sensor will measure a smaller force.

[0011] The sensors communicate the force measured in current or voltage differences and an amplifying system converts these values into signals for a computer where the data will be processed to elaborate statistical values, etc.

[0012] The data elaborated by the computer continuously inform about the pressing quality:

• Whether or not the load is stable. Load irregularities are discovered with percentage values thereof, for example: 80% correct load, 10% somewhat defective and 10% very defective.
• Whether the distribution of compaction is homogeneous and within the established limits thereof.

[0013] These same data are used to correct the load by means of the intelligent feed slide. A data package is elaborated and sent by communication cable to the microprocesser control of the intelligent slide to correct defective load areas.

[0014] As this data package is the statistical result of a series of pressings, there is no possibility of an erroneous correction as when the data are elaborated on the basis of samples taken by hand, as is presently done.

[0015] In order to permit a better understanding of the features of the invention and forming an integral part of this specification, a sheet of drawings in whose figures, with an illustrative and non-restrictive manner the following has been represented, is attached hereto:

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figures 1 and 2.- They schematically show the automatic control system of press compaction, when the sensors are located in the top punch and the positions before and after compaction, respectively, have been represented.

[0017] Figures 3 and 4.- They are schematic views similar to figures 1 and 2, with the sensors installed in the bottom punch.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018] 

[0019] Making reference to the numbering used in the figures, we can see how the automatic control system of press compaction, which the invention proposes, makes it possible to control the pressing of ceramic pieces of tile and pavement, by means of sensors (1) installed in the top punch (2) of the press. The ceramic granulate material (3) is located inside the mold (4) upon the bottom punch (5.)

[0020] References (6) and (7) respectively show the supports for the top punch (2) and bottom punch (5.)

[0021] In figures 1 and 2 we can see the sensors (1) located in the top punch (2), while in figures 3 and 4, we can see the same sensors (2) coupled to the bottom punch (5.)

[0022] When the granulate material (3) has been pressed, as shown in figures 2 and 4, irrespective of the fact whether the sensors (1) are located in the top punch (2) or in the bottom one (5), when the top punch penetrates into the mold (4) and compacts the granulate material, the sensors measure the reactive force of the granulate material, shown with vertical arrows that are directed towards the sensors (1.)

[0023] This force is measured in voltage differences, and an amplifying system converts these values into signals for a processor, in such a way that the data are processed to elaborate statistical values, etc. thus continuously informing about the pressing quality.

Claims

1. Automatic control system of press compaction, especially applicable in the manufacture of tiles and pavement, where the pieces are produced in dry presses, compacting a granulate material (3) with a specific moisture to endure drying, enameling, painting, belt conveyance treatments, and even kiln firing where the definitive resistance and feature are achieved, characterized because compaction data are obtained directly when pressing takes place, upon distributing pressure sensors (1) in the press mold itself, built in the top (2) or bottom (5) punch thereof, which makes it possible to control the load stability statistically, the sensors (1) communicating the force measured in voltage differences.

2. Automatic control system of press compaction, according to claim 1, characterized because there is an amplifying system that converts these values into signals for a computer, where the data will be processed to elaborate statistical values, etc., continuously informing about the pressing quality.

3. Automatic control system of press compaction, according to claim 1, characterized because the load correction is carried out by means of an intelligent feed slide that feeds the press, upon receiving the corresponding orders with value packages obtained by statistical evaluation.

Drawing