CN116428993A - Thickness measuring method for metal strip assembly line - Google Patents

Abstract

The invention discloses a method for measuring the thickness of a metal strip assembly line, which relates to the field of product parameter measurement and quality monitoring, and is implemented by an automatic detection system for the thickness of the metal strip. The automatic detection system for the thickness of the metal strip includes real-time sampling of the metal strip assembly line device and a background monitoring computing device, the measuring method specifically includes the following steps: establishing a sampling model reference, determining a sampling data computing model, determining a measurement offset and determining a light source receiving device; the present invention realizes the realization of the Real-time detection during the production process of metal strips, and a new measurement method is proposed. Through the synchronous measurement of the upper and lower planes, combined with the dynamic correction of the vibration deviation angle data, the measurement accuracy can be effectively improved.

Description

A method for measuring the thickness of metal strip assembly line

technical field

The invention relates to the field of product parameter measurement and quality monitoring, in particular to a method for measuring the thickness of a metal strip assembly line.

Background technique

With the rapid development of China's economy and the continuous improvement of the level of industrialization, metal strips are widely used in various links of industrial production. Professional measurement of materials to avoid waste of raw materials due to untimely measurement in the production process. In order to prevent the occurrence of the above phenomenon, sampling inspection is usually used for control, which cannot comprehensively improve the production pass rate, and there is still a lack of effective means for real-time monitoring of production conditions on the assembly line. At present, there are two related measurement methods:

One is the ultrasonic thickness measurement method: it measures the thickness according to the principle of ultrasonic pulse reflection. When the ultrasonic pulse emitted by the probe passes through the object to be measured and reaches the interface of the material, the pulse is reflected back to the probe. time to determine the thickness of the material to be tested; the second is the laser ultrasonic thin-layer material thickness detection method: the surface of the material is irradiated with laser pulses, and stress pulses are generated due to the thermoelastic effect. Propagate to the inside of the sample or along the surface, and characterize the defect through the reflection, scattering or attenuation of the ultrasonic wave, so as to obtain the thickness of the material.

Both of these two schemes have certain application effects, but there are still obvious deficiencies: the first method requires the measurement equipment to be attached to the object to be measured, and it is necessary to apply a coupling agent on the surface of the material to be tested during continuous measurement; the other This scheme is mainly used to measure the thickness of the coating or film layer, and lacks an accurate measurement basis for the thickness of the material itself;

For this reason, we propose a metal strip line thickness measurement method.

Contents of the invention

The purpose of the present invention is to propose a method for measuring the thickness of metal strips suitable for assembly lines, which can meet the measurement accuracy index required by the standard, and avoid the problem of waste of raw materials caused by untimely measurement in the production process.

In order to achieve the above object, the present invention adopts the following technical solutions:

A method for measuring the thickness of a metal strip assembly line, implemented by an automatic detection system for the thickness of metal strip, the automatic detection system for the thickness of metal strip includes a real-time sampling device and a background monitoring calculation device for the metal strip assembly line, the measurement method specifically includes the following step:

S1. Establish a sampling model benchmark: select a bracket structure with an overall height of H in the assembly line, arrange the laser emitting and receiving units at points A _t and A _b at the upper and lower ends of the structure, and the metal strip advances on the assembly line at a constant speed in the direction of the arrow ;

In an ideal state, the upper and lower planes of the strip are perpendicular to the laser, and affected by the vibration generated by the movement of the strip, the upper and lower planes of the strip form an angle θ with the horizontal plane;

S2. Determine the sampling data calculation model: the laser light source is incident vertically from point A _t above, and after being reflected by point B _t on the strip, it is received by point C _t . The time from light source emission to reception is t, and the distance from point A to point B is height h _t , the distance from point A to point C is the deviation radius r _t , then:

The distance traveled by light L _t =C×T _t , where C is the speed of light;

Existence relation: r _t ² +h _t ² =(L _t -h _t ) ² ;

then the height

The laser light source is vertically incident from point A _b below, and after being reflected by point B _b of the strip, it is received by point C _{b .} The distance is the deviation radius r _b

Therefore, the metal strip thickness D = Hh _t - h _b ;

S3. Determine the measurement offset: when the metal strip is transported, the vibration will cause a horizontal angle offset θ on the strip plane, and when the light is reflected, a reflection offset will be generated: r=h×tan2θ;

S4. Determine the light source receiving device: the light source receiving device should be designed to cover the offset range, and the lens radius should be ≥r.

As a further solution of the present invention: the design range of the height H in step S2 is 2.5 to 3.5m, and the speed of light is about 3×108m/s. If the resolution is to reach 1mm, the electronic circuit of the ranging sensor must be able to distinguish The following extremely short time is obtained: 0.001m/(3×108m/s)=3ps, to distinguish the time of 3ps, the existing laser displacement sensor cleverly avoids this obstacle, using the statistical principle, that is, the law of average The resolution of 1mm is realized, and the response speed can be guaranteed. The laser displacement sensor designed according to this principle can make the measurement accuracy reach 1μm within the range of 2m, which can meet the production demand.

As a further solution of the present invention: the vibration described in step S3 will cause the horizontal angle deviation θ of the strip plane to be determined: the vibration of the metal strip is mainly caused by the resultant force of the rolling friction force of the rotating shaft and the self-gravity of the strip during the operation of the conveyor belt As a result, the greater the rolling friction of the rotating shaft and the shorter the length of the suspended strip, the smallest vibration range.

Compared with the prior art, the beneficial effects of the present invention are:

(1) The assembly line thickness detection method of the metal strip of the present invention is different from the existing method of manual measurement, and realizes the real-time detection in the production process of the metal strip through automatic means and data analysis and calculation;

(2) The thickness detection method of the present invention proposes a new measurement method, through the synchronous measurement of the upper and lower planes, combined with the dynamic correction of the vibration deviation angle data, the measurement accuracy can be effectively improved.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the description, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute a limitation to the present invention.

Fig. 1 is the flow chart of a kind of metal strip assembly line thickness measuring method of the present invention;

Fig. 2 is the schematic diagram that the upper and lower planes of the strip and the horizontal plane form an angle of θ in the present embodiment;

FIG. 3 is a schematic diagram of a horizontal angular offset θ occurring in this embodiment.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention.

Example

Please refer to Figures 1-3, a method for measuring the thickness of a metal strip assembly line, which is implemented by an automatic detection system for the thickness of the metal strip. The automatic detection system for the thickness of the metal strip includes a real-time sampling device and a background monitoring and calculation device for the metal strip assembly line , the measurement method specifically includes the following steps:

First, establish the sampling model benchmark: Please refer to Figure 2, select a bracket structure with an overall height of H in the assembly line, arrange the laser transmitting and receiving units at points A _t and A _b at the upper and lower ends of the structure, and the metal strip along the direction of the arrow Advance at a constant speed on the assembly line;

In an ideal state, the upper and lower planes of the strip are perpendicular to the laser, and affected by the vibration generated by the movement of the strip, the upper and lower planes of the strip form an angle θ with the horizontal plane;

In order to reduce the vibration angle of the strip as much as possible, the measurement section is reduced, and three sections of 0.2m, 0.5m, and 1m are equipped with drive rollers for testing.

Secondly, determine the calculation model of the sampling data: the laser light source is incident vertically from point A _t above, and after being reflected by point B _t on the strip, it is received by point C _t . h _t , the distance from point A to point C is the deviation radius r _t , then:

The distance traveled by light L _t =C×T _t , where C is the speed of light;

Existence relation: r _t ² +h _t ² =(L _t -h _t ) ² ;

then the height

The laser light source is vertically incident from point A _b below, and after being reflected by point B _b of the strip, it is received by _point C _b . The distance is the deviation radius r _b

then the height

Therefore, the metal strip thickness D = Hh _t - h _b ;

The design range of the height H in this embodiment is 2.5-3.5m, and the speed of light is about 3×108m/s. If the resolution is to reach 1mm, the electronic circuit of the ranging sensor must be able to distinguish the following extremely short time : 0.001m/(3×108m/s)=3ps, to distinguish the time of 3ps, the existing laser displacement sensor cleverly avoids this obstacle, and uses the statistical principle, that is, the average law to achieve a resolution of 1mm , and can guarantee the response speed, the laser displacement sensor designed according to this principle can make the measurement accuracy reach 1μm within the range of 2m, which can meet the production demand.

Then, determine the measurement offset: Please refer to Figure 3. When the metal strip is transported, the vibration will cause the horizontal angle of the strip plane to shift θ, and when the light is reflected, a reflection offset will be generated: r=h×tan2θ , by adjusting the configuration of the transmission roller, determine the appropriate horizontal angle offset θ range;

It should be noted that the vibration will cause the horizontal angle deviation of the strip plane, and the range of the horizontal angle deviation θ is specifically determined as follows: when the conveyor belt is working, the vibration of the metal strip is mainly caused by the resultant force of the rolling friction of the rotating shaft and the gravity of the strip itself As a result, the greater the rolling friction of the rotating shaft and the shorter the length of the suspended strip, the smallest vibration range.

Finally, determine the light source receiving device: the light source receiving device should be designed to cover the offset range, and the lens radius should be ≥ r; when the metal strip is produced, the measuring device will measure the thickness of the strip in real time and sample the data to the production management end.

In summary, the detection method for the thickness of the metal strip in the assembly line of the present invention is different from the existing method of manual measurement, and realizes real-time detection in the production process of the metal strip through automatic means and data analysis and calculation; by proposing a A new measurement method, through the synchronous measurement of the upper and lower planes, combined with the dynamic correction of the vibration deviation angle data, can effectively improve the measurement accuracy.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the technical scope disclosed in the present invention, according to the technical solution of the present invention Any equivalent replacement or change of the inventive concepts thereof shall fall within the protection scope of the present invention.

Claims (3)

1. The thickness measuring method of the metal strip assembly line is implemented by a metal strip thickness automatic detection system, and the metal strip thickness automatic detection system comprises a real-time sampling device and a background monitoring and calculating device of the metal strip assembly line, and is characterized by comprising the following steps of:

s1, establishing a sampling model reference: selecting a support structure with the overall height H in a section of the assembly line, and arranging laser transmitting and receiving units at the upper end A and the lower end A of the structure _t Point and A _b The point is that the metal strip advances on the assembly line at a constant speed along the arrow direction;

in an ideal state, the upper and lower planes of the strip are in a vertical relation with the laser, and are influenced by vibration generated by movement of the strip, and the upper and lower planes of the strip form an angle theta with a horizontal plane;

s2, determining a sampling data calculation model: from above A _t Point vertical incidence laser source, via strip B _t After point reflection, by C _t Point receiving, wherein the time length from the light source to the light source is t, and the distance from the point A to the point B is the height h _t The distance from the point A to the point C is the deviation radius r _t Then:

distance L travelled by light _t ＝C×T _t C is the speed of light;

the relationship exists: r is (r) _t ² +h _t ² ＝(L _t -h _t ) ² ；

Height of then

From below A _b Point vertical incidence laser source, via strip B _b After point reflection, by C _b Point receiving, wherein the time length from the light source to the light source is t, and the distance from the point A to the point B is the height h _b The distance from the point A to the point C is the deviation radius r _b

Height of then

Thus, the metal strip thickness d=h-H _t -h _b ；

S3, determining a measurement offset: when the metal strip is transported, vibration causes the plane of the strip to generate horizontal angle deviation theta, and when light is reflected, reflection offset is generated: r=h×tan2θ;

s4, determining a light source receiving device: the light source receiving device is designed to cover the offset range, and the radius of the lens is preferably larger than or equal to r.

2. The method according to claim 1, wherein the height H in step S2 is designed to be 2.5-3.5 m, the speed of light is about 3 x 108m/S, and the electronic circuit of the distance measuring sensor must be able to distinguish the following very short time for the resolution to be 1 mm: 0.001 m/(3×108 m/s) =3ps, to distinguish the time of 3ps, the existing laser displacement sensor skillfully avoids the obstacle, achieves 1mm resolution by using a statistical principle, namely an average rule, can ensure response speed, and the laser displacement sensor designed according to the principle can enable measurement accuracy to reach 1 μm in a range of 2m, thereby meeting production requirements.

3. A method of thickness measurement of a metal strip line according to claim 1, wherein the vibration in step S3 causes a determination of the extent to which the strip plane is horizontally angularly offset θ: when the conveyor belt works, vibration of the metal strip is mainly caused by resultant force action of rolling friction force of the rotating shaft and self gravity of the strip, and when the length of the suspended strip is shorter, the vibration range is minimum.

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