CN203337113U - Three-dimensional microscopic light sectioning method surface roughness measuring instrument - Google Patents

Abstract

The utility model discloses a three-dimensional microscopic light sectioning method surface roughness measuring instrument. The instrument comprises a liftable objective table. A workpiece to be measured is placed on the liftable objective table. A microscopic imaging system is fixed right above the workpiece to be measured. The microscopic imaging system successively comprises an industrial CCD camera, a lens cone lens and an infinity correction microscope from top to bottom. A semiconductor laser is rotationally installed obliquely above the workpiece to be measured. The utility model discloses a non-contact measurement method. Measurement stability is good and maintenance is easy. After measuring instrument calibration is completed, a surface roughness value can be directly obtained. Calibration operation does not need to be performed repeatedly because materials and processing modes are different. The instrument is suitable for a plane or excircle surface of a metal component manufactured through processing modes of vehicle, milling, planning and the like. A measurement speed is fast. A surface roughness value Ra can be obtained only if one workpiece surface microstructure image is shot so that operation is easy.

Description

Three-dimensional micro-light cross-section method surfagauge

Technical field

The utility model relates to a kind of surfagauge that adopts three-dimensional micro-light cross-section method measurement piece surface microscopic appearance geometric parameter.

Background technology

Machined part surface exists to a certain degree both macro and micro error in geometrical form, and surfaceness is an index of reflection microcosmos geometric shape error, the i.e. high low degree of small peak valley and spacing situation thereof.The usability important of surfaceness to part, along with improving constantly of machine-building and detection automaticity, the detection of surfaceness causes people's attention day by day.Traditional contact pin type surfagauge, because it need to contact with measured surface, easily cause measured deviation because of mechanical wear.The model contrastive principle needs the customize standard sample, has greatly increased use cost, and uses difficulty large.

In the last few years, the optical means of novel measure surface roughness continued to bring out, and relied on its noncontact, did not damage the advantage of measured surface, had become the important trend of surface finish measurement technical development.At present, the common optical means for surface finish measurement has scattering method and speckle method, but their usable range are limited, and is a kind of method that compares and measures, and is not quantitative measurment, need to compare and just can obtain measurement result afterwards with standard jig.

The utility model content

The utility model purpose is exactly in order to make up the defect of prior art, provides a kind of three-dimensional micro-light cross-section method surfagauge.

The utility model is achieved through the following technical solutions:

The micro-light cross-section method surfagauge of a kind of three-dimensional, include the liftable objective table, be placed with workpiece for measurement on the liftable objective table, be fixed with micro imaging system directly over workpiece for measurement, described micro imaging system includes industrial CCD camera, tube lens and infinity correct microscope from top to bottom successively, and that at the oblique upper of workpiece for measurement, rotates is equipped with semiconductor laser.

Described semiconductor laser installing is on the adjustable mount pad of angle and position.

The utility model has the advantages that: the utility model is a kind of non-contacting measuring method, and Measurement sensibility is good, is easy to safeguard; After completing measuring instrument and demarcating, can directly obtain surface roughness value, without because of material and processing mode, difference repeatedly carrying out proving operation; Plane or the outer round surface of the metallic element of being applicable to car, milling, the processing mode such as plane being manufactured; Measuring speed is fast, as long as take the image of a width surface of the work microscopic appearance, can try to achieve surface roughness value Ra, easy operating.

The accompanying drawing explanation

Fig. 1 is structural representation of the present utility model.

Fig. 2 is the utility model principle of work schematic diagram.

Embodiment

As shown in Figure 1, the micro-light cross-section method surfagauge of a kind of three-dimensional, include the liftable objective table, be placed with workpiece for measurement 1 on the liftable objective table, be fixed with micro imaging system 2 directly over workpiece for measurement 1, described micro imaging system 2 includes industrial CCD camera 3, tube lens 4 and infinity correct microscope 5 from top to bottom successively, and that at the oblique upper of workpiece for measurement 1, rotates is equipped with semiconductor laser 6.

Described semiconductor laser 6 is arranged on the adjustable mount pad of angle and position.

In Fig. 1, at first the light that semiconductor laser 6 is launched the inner laser device collimate by collimating mirror, by beam expanding lens, expanded again, then by focus lamp, hot spot is focused to below 10 microns, focus is positioned at the surface of workpiece for measurement 1, finally with the aspheric surface beam expanding lens, light beam is expanded along a direction again, thereby form a long 5mm left and right and the wide laser striation 7 that is less than 10 μ m, and irradiate at a certain angle measured surface, be provided with angle and position regulator for the mount pad of semiconductor laser 6 in the present embodiment, can be according to measuring the position that needs to regulate laser striation 7.

Micro imaging system 2 in the present embodiment is comprised of infinity correct microscope 5, tube lens 4 and industrial CCD camera 3.During measurement, laser beam reflects through the workpiece measured surface, the infinity correct microscope 5 and tube lens 4 combinations that are less than 1 μ m by enlargement ratio 20, resolution are carried out imaging to described laser striation 7, the image of the reflection surface roughness profile become transfers to industrial computer after being gathered by industrial CCD camera 3, again through Digital Image Processing computing and mathematical computations, and finally obtain the surface roughness value Ra of measured surface.

The position of described micro imaging system 2 is fixed, and workpiece for measurement 1 is placed in to the liftable objective table, realizes thus the position adjustments of short transverse.Again in conjunction with the pose regulating device of above-mentioned semiconductor laser 6, before measurement, need carry out a series of angle and position adjusting operation, to reach, meet the pose requirement that the optical triangulation method is measured, obtain the microscopic appearance image at laser striation 7 places on measured surface clearly.

Referring to Fig. 2, the fundamental formular of the gauging surface microscopic appearance geometric parameter based on the optical triangulation method in the present embodiment is:

tanθ=h/d （1）

Wherein, the angle that θ is incident light and measured surface, the height that h is surface microscopic topographic, d is corrugation pitch.

The present embodiment need carry out by standard roughness gauge block the θ of calibration system, utilize the mode of micro-imaging to gather the sample image of standard roughness gauge block, and try to achieve corrugation pitch d by the Digital Image Processing computing, using the nominal value of standard roughness gauge block as h again, substitution formula (1), thus the θ value tried to achieve.Once demarcation, the pose of a described word line semiconductor laser 6 will be fixed, thus the θ value remain unchanged, thereby can be using tan θ as scale-up factor for the calculating of the microscopic appearance height h ＇ of measured surface, that is:

h＇=tanθ·d＇ （2）

Wherein, the corrugation pitch that d ＇ is the workpiece measured surface, can try to achieve by the calculating of the workpiece sample image to captured.

In order to improve the stated accuracy of above-mentioned scaling method, reduce impact measurement result caused because of calibrated error, the present embodiment will be asked for the θ value by the method for repeatedly measuring and reject maximum, minimum measured value.

The computing formula of the surface roughness Ra that the present embodiment adopts is:

$\mathrm{Ra}=\frac{1}{l}{\∫}_0^l\left|y\left(x\right)\right|\mathrm{dx}---\left(3\right)$

Be approximately,

$\mathrm{Ra}=\frac{1}{n}\underset{i=1}{\overset{n}{\mathrm{\Σ}}}\left|y_i\right|---\left(4\right)$

In formula:

On y (x)-surface profile, point is to the distance of datum line, i.e. h ＇ in formula (2);

Y _ii the distance of putting datum line on-surface profile;

L-sample length;

N-number of sampling.

Claims (2)

1. the micro-light cross-section method surfagauge of three-dimensional, it is characterized in that: include the liftable objective table, be placed with workpiece for measurement on the liftable objective table, be fixed with micro imaging system directly over workpiece for measurement, described micro imaging system includes industrial CCD camera, tube lens and infinity correct microscope from top to bottom successively, and that at the oblique upper of workpiece for measurement, rotates is equipped with semiconductor laser.

2. the micro-light cross-section method surfagauge of three-dimensional according to claim 1 is characterized in that: described semiconductor laser installing is on the adjustable mount pad of angle and position.

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