A high-precision material blank thickness detection device and detection method

Abstract

The present invention relates to the technical field of thickness detection, and discloses a high-precision blank thickness detection device and detection method, comprising a material guide table, wherein an inclined bottom plate is provided inside the material guide table, a fixed side plate symmetrically fixed on the front side of the material guide table is fixedly installed, a forming cylinder is rotatably installed between the two fixed side plates, the forming cylinder is fixedly connected to an external driving mechanism, and the rotation of the forming cylinder is controlled by the external driving mechanism, a left-right symmetrical support column is fixedly installed vertically upward on the material guide table, a connecting frame is fixedly welded between the two supporting columns, and a laser distance sensor is provided on the connecting frame. The signal processing unit measures the distance value from the laser distance sensor to the surface of the forming cylinder or from the laser distance sensor to the surface of the blank through the laser distance sensor, and performs Kalman filtering on all the measured distance values, and obtains the real-time measurement value of the blank thickness through calculation, which has the advantages of high measurement accuracy and no need for manual operation.

Description

Technical Field

[0001] The present invention relates to the technical field of thickness detection, and in particular to a high-precision blank thickness detection device and detection method. Background Art

[0002] During the board making process of calcium silicate board and fiber cement board, the blank flows out evenly after passing through the headbox and is spread on the running industrial blanket. After multi-stage water extraction, a thin layer of material surrounds the forming cylinder. When the set blank thickness is reached through multi-layer surrounding, the blank is actively cut out and transported to the blank receiving machine. At this time, the thickness of the blank on the forming cylinder directly determines whether the thickness of the board is qualified.

[0003] How to accurately measure the thickness of the blank on the forming cylinder in real time has become one of the key issues in building an automated production line for calcium silicate board and fiber cement board. Since the blank on the forming cylinder is surrounded by multiple layers of thin materials, the contact thickness measurement method will damage the surface of the blank. In most calcium silicate board and fiber cement board production lines, non-contact laser ranging method is used to measure the thickness of the blank on the forming cylinder.

[0004] When there is no blank on the forming cylinder, the laser distance sensor measures the distance between it and the empty surface of the forming cylinder. When there is a blank, the laser distance sensor measures the distance between it and the surface of the blank on the forming cylinder. The difference between the two detected distance values ​​is the thickness of the blank on the forming cylinder. Ideally, the value detected when there is no blank on the forming cylinder is constant, while the value detected when there is a blank changes in a step-like manner. However, in the actual production process, when there is no blank, the surface of the forming cylinder is uneven, and there are slight differences in the distances from each laser sensor to the forming cylinder. When there is a blank, the surface of the blank is uneven, the frame vibrates irregularly, and other factors will cause the detection value of the laser distance sensor to jump greatly, resulting in the inability to accurately calculate the thickness of the blank.

[0005] Therefore, we propose a high-precision billet thickness detection device and detection method. Summary of the invention

[0006] The present invention mainly solves the technical problems existing in the above-mentioned prior art and provides a high-precision blank thickness detection device and detection method.

[0007] In order to achieve the above-mentioned object, the present invention adopts the following technical scheme: a high-precision blank thickness detection device, comprising a material guide table, an inclined bottom plate is provided inside the material guide table, a fixed side plate symmetrically fixed to the front side of the material guide table is fixedly installed, and a forming cylinder is rotatably installed between the two fixed side plates;

[0008] The guide table is vertically fixed with left-right symmetrical support columns, a connecting frame is fixedly welded between the two support columns, an L-shaped wire tube is fixedly installed on the front side of the connecting frame, and a laser distance sensor is provided at the lower end of the L-shaped wire tube;

[0009] A signal processing unit is fixedly mounted on the side wall surface of the material guiding platform.

[0010] Preferably, the inclined bottom plate is arranged to be gradually inclined downward toward a side close to the forming tube.

[0011] Preferably, a buffer seat is fixedly sleeved on the support column, and the connecting frame is distributed just above the forming cylinder.

[0012] Preferably, there are multiple groups of laser ranging sensors, which are arranged equidistantly from left to right. A horizontal wire tube that is interconnected with the L-shaped wire tube is fixedly installed on the side wall of the connecting frame. A connecting wire is provided on the laser ranging sensor. The multiple groups of connecting wires are collected into the interior of the horizontal wire tube through the L-shaped wire tube and extend outward through the external port of the horizontal wire tube to be connected to the signal processing unit.

[0013] Preferably, one end of the connecting line away from the horizontal line tube is connected to the inside of a signal processing unit, and a display module is provided on the signal processing unit.

[0014] The present invention also provides a high-precision blank thickness detection method, comprising the following method steps:

[0015] Sp1: The signal processing unit measures the distance values ​​from n laser distance measuring sensors to the surface of the forming cylinder or from the laser distance measuring sensor to the surface of the blank through the laser distance measuring sensor, and performs Kalman filtering on the measured n distance values, and records the filtered n distance values ​​as x1, x2, x3...x m , x m+1 ……x n , jump to Sp2;

[0016] Sp2: Subtract the previous value from the next value in the filtered distance value sequence to obtain a sequence of distance difference values ​​Δ1, Δ2, Δ3...Δ m , Δ m+1 ……Δ n-1; Determine whether there is a distance difference exceeding the threshold. If so, define the latter distance value of the two distance values ​​corresponding to the distance difference as a mutation value; if the distance difference is positive, define it as a mutation steep increase; if the distance difference is negative, define it as a mutation sudden decrease; if a mutation steep increase is searched in n distance values, jump to Sp3; if a mutation sudden decrease is searched in n distance values, jump to Sp4; if no mutation value is searched in n distance values, jump to Sp1;

[0017] Sp3: Search whether there is a sudden decrease value in the distance value between the current sudden steep increase value and the nth distance value. If yes, jump to Sp4; if not, jump to Sp1;

[0018] Sp4: If the last mutation value is a steep increase, take the average of all distance values ​​between the steep increase and the sudden decrease. The average value is the distance value from the laser distance sensor to the surface of the forming tube, which is defined as the reference distance value and jumps to Sp1; if the last mutation value is a sudden decrease, jump to Sp5;

[0019] Sp5: Average all distance values ​​between two sudden drop values, subtract the average distance value from the reference distance value, and you can get the real-time thickness value of the blank on the forming cylinder, and jump to Sp1.

[0020] Beneficial Effects

[0021] The present invention provides a high-precision material thickness detection device and detection method. It has the following beneficial effects:

[0022] (1) The present invention can adaptively measure the distance value from the laser distance sensor to the surface of the forming tube, i.e., the reference distance value, and can also adaptively measure the distance value from the laser distance sensor to the surface of the blank. By subtracting the distance value from the laser distance sensor to the surface of the blank from the reference distance value, the real-time thickness value of the blank on the forming tube can be obtained. The entire measurement process does not require human intervention.

[0023] (2) The present invention performs Kalman filtering on all measured distance values. When there is no billet, the surface of the forming cylinder is uneven and there are slight differences in the distances from each laser sensor to the forming cylinder. When there is a billet, the surface of the billet is uneven and the frame vibrates irregularly. The thickness of the billet can be accurately measured.

[0024] (3) Compared with the measurement method using the traditional distance measuring sensor, the present invention does not require manual operation, which can reduce the frequency of manual re-inspection of the thickness of the blank and reduce the workload of workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the implementation of the present invention or the technical solution in the prior art, the following briefly introduces the drawings required for the implementation or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0026] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0027] Figure 1 It is a schematic diagram of the overall three-dimensional structure of the present invention;

[0028] Figure 2 This is a schematic diagram of the position structure of the laser ranging sensor of the present invention;

[0029] Figure 3 This is a block diagram of the working principle of the signal processing unit of the present invention.

[0030] Legend:

[0031] 1. Material guide table; 2. Inclined bottom plate; 3. Fixed side plate; 4. Forming cylinder; 5. Buffer seat; 6. Support column; 7. Connecting frame; 8. L-shaped wire tube; 9. Laser ranging sensor; 10. Horizontal wire tube; 11. Connecting wire; 12. Signal processing unit; 13. Display module. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] A high-precision material thickness detection device, such as Figure 1-Figure 3As shown, it includes a material guiding platform 1, an inclined bottom plate 2 is provided inside the material guiding platform 1, and fixed side plates 3 are fixedly installed on the front side of the material guiding platform 1, and a forming cylinder 4 is rotatably installed between the two fixed side plates 3. The forming cylinder 4 is fixedly connected to an external driving mechanism, and the rotation of the forming cylinder 4 is controlled by the external driving mechanism. The inclined bottom plate 2 is gradually inclined downward toward the side close to the forming cylinder 4, and the material is guided to the forming cylinder 4 through the inclined bottom plate 2, and the material is adhered by the forming cylinder 4 to form a blank.

[0034] A left-right symmetrical support column 6 is fixedly installed vertically upward on the material guide table 1, a buffer seat 5 is fixedly sleeved on the support column 6, a connecting frame 7 is fixedly welded between the two support columns 6, the connecting frame 7 is distributed just above the forming tube 4, an L-shaped wire tube 8 is fixedly installed on the front side of the connecting frame 7, a laser distance measuring sensor 9 is provided at the lower end of the L-shaped wire tube 8, there are multiple groups of laser distance measuring sensors 9, and the multiple groups of laser distance measuring sensors 9 are arranged equidistantly from left to right, a horizontal wire tube 10 connected to the L-shaped wire tube 8 is fixedly installed on the side wall of the connecting frame 7, a connecting line 11 is provided on the laser distance measuring sensor 9, multiple groups of connecting lines 11 are collected into the interior of the horizontal wire tube 10 through the L-shaped wire tube 8 and extend outward through the outer port of the horizontal wire tube 10.

[0035] A signal processing unit 12 is fixedly installed on the side wall of the material guide table 1, and the end of the connecting line 11 away from the horizontal line tube 10 is connected to the inside of the signal processing unit 12. The laser ranging sensor 9 transmits the detected data to the inside of the signal processing unit 12 through the connecting line 11. The signal processing unit 12 is provided with a display module 13.

[0036] A high-precision billet thickness detection method is used, taking a billet with a small layer thickness of 1 mm and wrapped 4 times on a forming cylinder as an example. The specific measurement and calculation steps are as follows:

[0037] Sp1: The signal processing unit measures the distance values ​​from n laser distance measuring sensors to the surface of the forming cylinder or from the laser distance measuring sensor to the surface of the blank through the laser distance measuring sensor, and performs Kalman filtering on the measured n distance values, and records the filtered n distance values ​​as x1, x2, x3...x m , x m+1 ……x n , jump to Sp2;

[0038] Sp2: Subtract the previous value from the next value in the filtered distance value sequence to obtain a sequence of distance difference values ​​Δ1, Δ2, Δ3...Δ m , Δ m+1 ……Δ n-1; Determine whether there is a distance difference exceeding the threshold. If so, define the latter distance value of the two distance values ​​corresponding to the distance difference as a mutation value; if the distance difference is positive, define it as a mutation steep increase; if the distance difference is negative, define it as a mutation sudden decrease; if a mutation steep increase is searched in n distance values, jump to Sp3; if a mutation sudden decrease is searched in n distance values, jump to Sp4; if no mutation value is searched in n distance values, jump to Sp1;

[0039] Sp3: Search whether there is a sudden decrease value in the distance value between the current sudden steep increase value and the nth distance value. If yes, jump to Sp4; if not, jump to Sp1;

[0040] Sp4: If the last mutation value is a steep increase, take the average of all distance values ​​between the steep increase and the sudden decrease. The average value is the distance value from the laser distance sensor to the surface of the forming tube, which is defined as the reference distance value and jumps to Sp1; if the last mutation value is a sudden decrease, jump to Sp5;

[0041] Sp5: Average all distance values ​​between two sudden drop values, subtract the average distance value from the reference distance value, and you can get the real-time thickness value of the blank on the forming cylinder, and jump to Sp1.

[0042] This method can adaptively measure the distance value from the laser distance sensor to the surface of the forming cylinder, that is, the reference distance value. At the same time, it can also adaptively measure the distance value from the laser distance sensor to the surface of the blank. By subtracting the distance value from the laser distance sensor to the surface of the blank from the reference distance value, the real-time thickness value of the blank on the forming cylinder can be obtained. The real-time thickness value has high accuracy, and the entire measurement process does not require human intervention, which can reduce the frequency of manual re-inspection of the blank thickness and reduce the workload of workers.

[0043] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A high-precision billet thickness detection method, characterized in that: The method comprises the following steps: Sp1: The signal processing unit measures the distance values ​​from n laser distance sensors to the surface of the forming cylinder or from the laser distance sensor to the surface of the blank through the laser distance sensor, and performs Kalman filtering on the measured n distance values, and records the n distance values ​​after filtering as x1, x2, x3...x m , x m+1 ……x n , jump to Sp2; where m is not greater than n and both are positive integers; Sp2: Subtract the previous value from the next value in the filtered distance value sequence to obtain a sequence of distance difference values ​​Δ1, Δ2, Δ3...Δ m , Δ m+1 ……Δ n-1 ; Determine whether there is a distance difference exceeding the threshold. If so, define the latter distance value of the two distance values ​​corresponding to the distance difference as a mutation value; if the distance difference is positive, define it as a mutation steep increase; if the distance difference is negative, define it as a mutation sudden decrease; if a mutation steep increase is searched in n distance values, jump to Sp3; if a mutation sudden decrease is searched in n distance values, jump to Sp4; if no mutation value is searched in n distance values, jump to Sp1; Sp3: Search whether there is a sudden decrease value in the distance value between the current sudden steep increase value and the nth distance value. If yes, jump to Sp4; if not, jump to Sp1; Sp4: If the last mutation value is a steep increase, take the average of all distance values ​​between the steep increase and the sudden decrease. The average value is the distance value from the laser distance sensor to the surface of the forming tube, which is defined as the reference distance value and jumps to Sp1; if the last mutation value is a sudden decrease, jump to Sp5; Sp5: average all distance values ​​between two sudden drop values, subtract the average distance value from the reference distance value, and you can get the real-time thickness value of the blank on the forming cylinder, and jump to Sp1; The detection method adopts a high-precision blank thickness detection device, comprising a material guide table (1), wherein an inclined bottom plate (2) is provided inside the material guide table (1), and a left-right symmetrical fixed side plate (3) is fixedly installed on the front side of the material guide table (1), and a forming cylinder (4) is rotatably installed between the two fixed side plates (3); The guide platform (1) is vertically and upwardly fixedly provided with left-right symmetrical support columns (6), a connecting frame (7) is fixedly welded between the two support columns (6), an L-shaped wire tube (8) is fixedly provided on the front side of the connecting frame (7), and a plurality of groups of laser distance measuring sensors (9) are provided at the lower end of the L-shaped wire tube (8); A signal processing unit (12) is fixedly mounted on the side wall surface of the material guiding platform (1).

2. A high-precision blank thickness detection method according to claim 1, characterized in that: The inclined bottom plate (2) is arranged to be gradually inclined downwards towards a side close to the forming cylinder (4).

3. A high-precision blank thickness detection method according to claim 1, characterized in that: A buffer seat (5) is fixedly sleeved on the support column (6), and a connecting frame (7) is distributed just above the forming cylinder (4).

4. A high-precision blank thickness detection method according to claim 1, characterized in that: The laser distance measuring sensors (9) are provided with a plurality of groups, and the plurality of groups of laser distance measuring sensors (9) are arranged in sequence at equal intervals from left to right. A horizontal line tube (10) which is interconnected with the L-shaped line tube (8) is fixedly mounted on the side wall surface of the connecting frame (7). A connecting line (11) is provided on the laser distance measuring sensor (9). The plurality of groups of connecting lines (11) are collected into the interior of the horizontal line tube (10) through the L-shaped line tube (8) and extend outward through the external port of the horizontal line tube (10) to be connected to the signal processing unit (12).

5. A high-precision blank thickness detection method according to claim 4, characterized in that: One end of the connection line (11) away from the horizontal line tube (10) is connected to the inside of a signal processing unit (12), and a display module (13) is provided on the signal processing unit (12).

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