CN105043278A - Non-contact and multi-point measurement method for measuring internal diameter of circular hole - Google Patents

Abstract

The invention provides a non-contact and multi-point measurement method for measuring the internal diameter of a circular hole. The method comprises the steps of constructing a three-sensor/four-sensor constant-value comparison and measurement head; adjusting the measurement optical axis of a laser displacement sensor and meeting preset conditions before measurement and after measurement respectively; and acquiring the radius of a to-be-measured circular hole. According to the technical scheme of the invention, the non-contact constant-value comparison and measurement method is adopted, and a non-contact measurement head is kept far away from the surface of a to-be-measured object. The measurement safety is improved. When the aperture of an inner hole on a workpiece is measured, the measurement head is placed in the to-be-measured hole to complete the measurement. Therefore, the centering or adjusting operation is avoided, and the measurement efficiency is greatly improved.

Description

A kind of method of contactless multimetering circular hole internal diameter

Technical field

The present invention relates to geometric measurement field, particularly relate to a kind of method of contactless multimetering circular hole internal diameter.

Background technology

Along with the fast development of China's industrial manufacturing industry, the effect of precision measurement equipment in industrial manufacturing process becomes ever more important, and Aero-Space, shipbuilding make the fields such as warship, engine and turbine all needs geometric measurement technology as effective support.Whenever needs are when manufacturing in-site measurement workpiece, nearly all can in the face of the on-machine measurement problem of inner hole of workpiece diameter.Traditional diameter of bore measuring method, mainly contains: milscale, universal comparator, Abbe horizontal metroscope, dial gauge.These methods need to measure manually mostly, measure efficiency low and introduce personal error, be difficult to realize robotization.In addition, novel measuring method also has a lot, mainly contains at present: air-gauge, three coordinate measuring machine and image measurer etc.But three coordinate measuring machine and image measurer cannot realize On-machine Test, carrying workpiece needs at substantial man-hour, to be unfavorable for enhancing productivity.Although air-gauge can be implemented in machine and measures, need manual hand manipulation, measure efficiency low.The more important thing is, due to the restriction of working distance, measurer easily and measured piece collide, cause damage.

Circular hole internal diameter in machine, precision, automatic measurement problem, be a difficult problem for China's industry manufacture field always., mainly there is following difficult point in comprehensive above background:

1, the operational issue of surveying instrument: inside diameter measurement, due to by space and tested quantitative limitation, only simply cannot be installed in outside and just can measure, be difficult to realize robotization as outside dimension is measured.

2, the problem of measuring accuracy: the precision measurement how realizing circular hole internal diameter is problem demanding prompt solution always.

3, about the problem measuring efficiency.On-machine measurement can save machining period, but still there is the rapidity problem of measuring method.Traditional on-machine measurement means, most employing is measured manually.Measurement efficiency is low, and quantity of information is not enough, and human factor impact is larger.Therefore, seek bore diameter measuring method to be fast and effectively of great immediate significance.

Summary of the invention

The invention provides a kind of method of contactless multimetering circular hole internal diameter, the present invention adopts definite value to compare and measure mode, can measure circular hole internal diameter rapidly and accurately, described below:

A method for contactless multimetering circular hole internal diameter, the method for described measurement circular hole internal diameter comprises the following steps:

Build three sensor definite values and compare and measure head;

The measurement optical axis of laser displacement sensor is adjusted, respectively meet first measure before and measure time pre-conditioned;

Tested circular hole is constructed leg-of-mutton circumscribed circle, obtains the radius of tested circular hole according to external Triangle Formula.

Wherein, described three sensor definite values compare and measure head and comprise: measuring head bottom surface shaft collar, described measuring head bottom surface shaft collar is provided with measuring head axis, described measuring head axis is socketed with angle and range adjustment disk, described angle and range adjustment disk are provided with fixing and adjustment hole, described measuring head axis is provided with three fixing rack for sensor, described fixing rack for sensor is provided with laser displacement sensor, described laser displacement sensor is provided with sensor and fixes and adjusting screw.

Wherein, the top of described measuring head axis is provided with shaft adapter in measuring head, and in described measuring head, shaft adapter is connected with measuring head connecting link, and described measuring head connecting link is used for being connected with machine tool chief axis; The sidewall of described measuring head axis is provided with data and power lead through hole.

Further, described laser displacement sensor is provided with adjustment disk connecting screw; Described laser displacement sensor is laser triangulation displacement sensor.

Further, described first measure before be pre-conditionedly: the measurement optical axis adjusting three laser displacement sensors respectively, make three to measure optical axis at grade, and three extended lines measuring optical axis meet at a bit, three are measured optical axis angle is between any two 120 °; Described first pre-conditionedly when measuring is: three sensor definite values are compared and measured head and be placed in the inner optional position of circular hole, adjust three sensor definite values and compare and measure head, making three to measure optical axis is positioned on the normal section of circular hole, with the center of circle of tested circular hole for true origin, builds X-Y coordinate axis.

Another embodiment, a kind of method of contactless multimetering circular hole internal diameter, the method for described measurement circular hole internal diameter comprises the following steps:

Build four-sensor definite value and compare and measure head;

The measurement optical axis of laser displacement sensor is adjusted, respectively meet second measure before and measure time pre-conditioned;

Obtain the radius of tested circular hole.

Wherein, described four-sensor definite value compares and measures head and comprises: measuring head bottom surface shaft collar,

Described measuring head bottom surface shaft collar is provided with measuring head axis, described measuring head axis is socketed with angle and range adjustment disk, described angle and range adjustment disk are provided with fixing and adjustment hole, described measuring head axis is provided with four fixing rack for sensor, described fixing rack for sensor is provided with laser displacement sensor, described laser displacement sensor is provided with sensor and fixes and adjusting screw.

Wherein, the top of described measuring head axis is provided with shaft adapter in measuring head, and in described measuring head, shaft adapter is connected with measuring head connecting link, and described measuring head connecting link is used for being connected with machine tool chief axis; The sidewall of described measuring head axis is provided with data and power lead through hole.

Further, described laser displacement sensor is provided with adjustment disk connecting screw; Described laser displacement sensor is laser triangulation displacement sensor.

Further, described second measure before be pre-conditionedly: the measurement optical axis adjusting four laser displacement sensors respectively, four are made to measure optical axis at grade, and four extended lines measuring optical axis meet at a bit, adjacent two are measured optical axis included angle is 90 °, and relative two are measured optical axis point-blank;

Described first pre-conditionedly when measuring is: four-sensor definite value is compared and measured head and be placed in the inner optional position of circular hole, adjustment four-sensor definite value compares and measures head, four planes measuring optical axis place are made to be positioned on the normal section of circular hole, with the center of circle of tested circular hole for true origin, build X-Y coordinate axis.

The beneficial effect of technical scheme provided by the invention is:

1, measure security: contact type measurement General Requirements operating personnel are positioned at and measure operation, reading or guiding near key element, be difficult to realize automatically measuring.What this method adopted is contactless definite value comparative measurement method, and non-cpntact measurement head, away from measured object surface, improves the security of measurement.

2, measurement precision: adopt high precision laser displacement sensor, the distance of measured object to sensor can be measured quickly and accurately; Adopt definite value comparative measurement method, greatly reduce error chain, be conducive to improving measuring accuracy.

3, operation ease: during this method measuring workpieces endoporus aperture, as long as be placed in measuring head in tested aperture.Without the need to the operation such as the heart, adjustment, substantially increase measurement efficiency.

4, can on-machine measurement be realized: be arranged on lathe by non-cpntact measurement head, utilize the movement executing mechanism of lathe self, can realize in machine precision measurement.

Accompanying drawing explanation

Fig. 1 is the structural drawing that three sensor definite values compare and measure head;

Fig. 2 is laser displacement sensor measuring head middle shaft structure figure;

Fig. 3 is laser displacement sensor and fixed mount constitutional diagram;

Fig. 4 is 3 measurement model figure measuring Circularhole diameter;

Fig. 5 is the structural drawing that four-sensor definite value compares and measures head;

Fig. 6 is disassemblying structure figure bottom four-sensor measuring head;

Fig. 7 is 4 measurement model figure measuring Circularhole diameter.

Shown in accompanying drawing, components listed is listed as follows:

1, measuring head connecting link; 2, angle and range adjustment disk;

3, fixing and adjustment hole; 4, sensor is fixed and adjusting screw;

5, laser displacement sensor; 6, fixing rack for sensor;

7, measuring head bottom surface shaft collar; 8, measuring head axis;

9, shaft adapter in measuring head; 10, data and power lead through hole;

11, laser beam; 12, adjustment disk connecting screw.

Embodiment

For making the object, technical solutions and advantages of the present invention clearly, below in conjunction with accompanying drawing, embodiment of the present invention is described further in detail.

Embodiment 1

A method for contactless multimetering circular hole internal diameter, see Fig. 1, Fig. 2, Fig. 3 and Fig. 4, the method for this measurement circular hole internal diameter comprises the following steps:

101: build three sensor definite values and compare and measure head;

See Fig. 1 and Fig. 2, three sensor definite values compare and measure head and comprise: measuring head bottom surface shaft collar 7, measuring head bottom surface shaft collar 7 is provided with measuring head axis 8, measuring head axis 8 is socketed with angle and range adjustment disk 2, angle and range adjustment disk 2 are provided with fixing and adjustment hole 3, measuring head axis 8 is provided with three fixing rack for sensor 6, fixing rack for sensor 6 is provided with laser displacement sensor 5, laser displacement sensor 5 is provided with sensor and fixes and adjusting screw 4.

See Fig. 2, the top of measuring head axis 8 is provided with shaft adapter 9 in measuring head, and in measuring head, shaft adapter 9 is connected with measuring head connecting link 1, and measuring head connecting link 1 is for being connected with machine tool chief axis; The sidewall of measuring head axis 8 is provided with data and power lead through hole 10.

See Fig. 3, laser displacement sensor 5 is provided with adjustment disk connecting screw 12, laser displacement sensor 5 Emission Lasers light beam 11.

Wherein, laser displacement sensor preferred laser triangulation displacement sensor.

102: the measurement optical axis of laser displacement sensor is adjusted, respectively meet first measure before and measure time pre-conditioned;

See Fig. 4, before measurement, adjust the measurement optical axis (P of three laser displacement sensors 5 respectively ₁a, P ₂b and P ₃c), three are made to measure optical axis at grade, and three extended lines measuring optical axis meet at 1 O (namely O point expression three laser displacement sensors measure the center of optical axis), three are measured optical axis angle is between any two 120 ° of (i.e. P ₁a and P ₂angle between B is 120 °; P ₁a and P ₃angle between C is 120 °; P ₂b and P ₃angle between C is 120 °).

See Fig. 4, if the center of circle of tested circular hole is O ₁point, and with O ₁point is initial point, sets up X-Y coordinate axis.During measurement, three sensor definite values are compared and measured head and be placed in the inner optional position of tested circular hole, adjust three sensor definite values and compare and measure head, make three to measure optical axis (P ₁a, P ₂b and P ₃c) be positioned on the normal section of tested circular hole, now, O ₁point is the center of circle of tested circular hole.

103: tested circular hole is the circumscribed circle of triangle ABC, obtains the radius of tested circular hole according to external Triangle Formula.

See Fig. 4, measure optical axis P ₁a, P ₂b and P ₃p in C ₁, P ₂and P ₃represent the measurement starting point of three laser displacement sensors respectively; A, B and C represent that laser beam 11 penetrates the measurement point on tested circular hole respectively; Measure optical axis P ₁a, P ₂b and P ₃c is also expressed as the measured value of three laser displacement sensors.OP ₁, OP ₂and OP ₃be expressed as the distance of range starting point to three measuring beam intersection points of three laser displacement sensors, can by demarcate (by the circular hole of the known internal diameter of repetitive measurement, can reverse OP ₁, OP ₂and OP ₃length) obtain, i.e. OP ₁, OP ₂and OP ₃known.

If the radius of tested circular hole is R, S is leg-of-mutton area, the radius of tested circular hole can be determined according to external Triangle Formula:

$R=\frac{\mathrm{AB}\·\mathrm{BC}\·\mathrm{AC}}{S}---\left(1\right)$

According to Heron's formula:

$S=\sqrt{(\mathrm{AB}+\mathrm{AC}+\mathrm{BC})(\mathrm{AB}+\mathrm{AC}-\mathrm{BC})(-\mathrm{AB}+\mathrm{AC}+\mathrm{BC})(\mathrm{AB}-\mathrm{AC}+\mathrm{BC})}---\left(2\right)$

Have:

$R=\frac{\mathrm{AB}\·\mathrm{BC}\·\mathrm{AC}}{\sqrt{(\mathrm{AB}+\mathrm{AC}+\mathrm{BC})(\mathrm{AB}+\mathrm{AC}-\mathrm{BC})(-\mathrm{AB}+\mathrm{AC}+\mathrm{BC})(\mathrm{AB}-\mathrm{AC}+\mathrm{BC})}}---\left(3\right)$

According to the cosine law, have:

$AC=\sqrt{{\mathrm{OA}}^2+{\mathrm{OC}}^2-OA\·OC\·cos\frac{4\mathrm{\π}}{3}}=\sqrt{{\mathrm{OA}}^2+{\mathrm{OC}}^2+\frac{1}{2}\·OA\·OC}---\left(4\right)$

In like manner:

$\begin{array}{c}\mathrm{BC}=\sqrt{{\mathrm{OB}}^2+{\mathrm{OC}}^2+\frac{1}{2}\·\mathrm{OB}\·\mathrm{OC}}\\ \mathrm{AB}=\sqrt{{\mathrm{OB}}^2+{\mathrm{OA}}^2+\frac{1}{2}\·\mathrm{OB}\·\mathrm{OA}}\end{array}---\left(5\right)$

Because:

$\left\{\begin{array}{c}\mathrm{OA}={\mathrm{OP}}_1+P_{1}A\\ \mathrm{OB}={\mathrm{OP}}_2+P_{2}B\\ \mathrm{OC}={\mathrm{OP}}_3+P_{3}C\end{array}\right.---\left(6\right)$

Wherein, OA, OB, OC are measurement point A, B, C distances to the extending line intersection point O of measurement optical axis.Therefore, the radius R of tested circular hole can be asked.

During real work, first measuring head connecting link 1 is arranged in the mechanism with translation function, forms the measuring system of complete set, and three sensor definite values being compared and measured head, to be placed in tested circular hole inner, measures optical axis (P for three ₁a, P ₂b and P ₃c) be positioned on the normal section of circular hole, can obtain the radius measurement of tested circular hole, whole measuring process is simple, quick.The three sensor definite values built by the embodiment of the present invention compare and measure head, and measuring method high-precisionly can get the radius of tested circular hole.

Embodiment 2

A method for contactless multimetering circular hole internal diameter, see Fig. 2, Fig. 3, Fig. 5, Fig. 6 and Fig. 7, the method for this measurement circular hole internal diameter comprises the following steps:

201: build four-sensor definite value and compare and measure head;

See Fig. 1, Fig. 5 and Fig. 6, four-sensor definite value compares and measures head and comprises: measuring head bottom surface shaft collar 7, measuring head bottom surface shaft collar 7 is provided with measuring head axis 8, measuring head axis 8 is socketed with angle and range adjustment disk 2, angle and range adjustment disk 2 are provided with fixing and adjustment hole 3, measuring head axis 8 is provided with four fixing rack for sensor 6, each fixing rack for sensor 6 is provided with laser displacement sensor 5, laser displacement sensor 5 is provided with sensor and fixes and adjusting screw 4.

Namely four-sensor definite value compares and measures head and is only with the difference that three sensor definite values compare and measure head: fixing rack for sensor 6, laser displacement sensor 5 and fixing different with the quantity of adjustment hole 3, all the other structures are all identical.

See Fig. 2, the top of measuring head axis 8 is provided with shaft adapter 9 in measuring head, and in measuring head, shaft adapter 9 is connected with measuring head connecting link 1, and measuring head connecting link 1 is for being connected with machine tool chief axis; The sidewall of measuring head axis 8 is provided with data and power lead through hole 10.

See Fig. 3, laser displacement sensor 5 is provided with adjustment disk connecting screw 12, laser displacement sensor 5 sends laser beam 11.

Wherein, laser displacement sensor preferred laser triangulation displacement sensor.

202: the measurement optical axis of laser displacement sensor is adjusted, respectively meet second measure before and measure time pre-conditioned;

See Fig. 7, before measurement, adjust the measurement optical axis (P of four laser displacement sensors 5 respectively ₁a, P ₂b, P ₃c and P ₄d), four are made to measure optical axis at grade, and four are measured the extended lines of optical axises and meet at 1 O (namely O point expression four laser displacement sensors measure the center of optical axises), two adjacent measurement optical axis included angles be 90 ° (such as: measurement optical axis P ₁a and P ₄angle between D is 90 °, P ₂b and P ₃angle between C is 90 °), and relative two are measured optical axis point-blank (such as: measure optical axis P ₁a and P ₂b point-blank, P ₃c and P ₄d point-blank).

See Fig. 7, during measurement, four-sensor definite value is compared and measured head and be placed in the inner optional position of tested circular hole, adjustment four-sensor definite value compares and measures head, makes four to measure optical axis (P ₁a, P ₂b, P ₃c and P ₄d) plane at place is positioned on the normal section of tested circular hole, now, and O ₁point is the center of circle of tested circular hole.

203: the radius obtaining tested circular hole;

See Fig. 7, measure optical axis P ₁a, P ₂b, P ₃c and P ₄p in D ₁, P ₂, P ₃and P ₄represent the measurement starting point of four laser displacement sensors 5 respectively; A, B, C and D represent the measurement point of four laser displacement sensors respectively; Measure optical axis P ₁a, P ₂b, P ₃c and P ₃d is also expressed as the measured value of four laser displacement sensors.OP ₁, OP ₂, OP ₃and OP ₄be expressed as the distance of range starting point to four measuring beam intersection points of four sensors, can be obtained by demarcation (see embodiment 1, the present embodiment does not repeat this concrete step of demarcating), i.e. OP ₁, OP ₂, OP ₃and OP ₄known.

If circle hole radius is R, then have:

$R^2=\frac{1}{4}[{(O_{1}A+O_{1}B)}^2+{(O_{1}C-O_{1}D)}^2]---\left(7\right)$

$R^2=\frac{1}{4}[{(O_{1}B-O_{1}A)}^2+{(O_{1}C+O_{1}D)}^2]---\left(8\right)$

In conjunction with formula (7) and (8), have:

R ²＝1/4(O ₁B ²+O ₁A ²+O ₁C ²+O ₁D ²)(9)

Known

$\left\{\begin{array}{c}\mathrm{OA}={\mathrm{OP}}_1+P_{1}A\\ \mathrm{OB}={\mathrm{OP}}_2+P_{2}B\\ \mathrm{OC}={\mathrm{OP}}_3+P_{3}B\\ \mathrm{OD}={\mathrm{OP}}_4+P_{4}B\end{array}\right.---\left(10\right)$

Wherein, OA, OB, OC and OD are measurement point A, B, C, D distances to the extending line intersection point O of measurement optical axis.Therefore, the radius R of tested circular hole can be asked.

During real work, first measuring head connecting link 1 is arranged in the mechanism with translation function, forms the measuring system of complete set, and four-sensor definite value being compared and measured head, to be placed in tested circular hole inner, measures optical axis (P for four ₁a, P ₂b, P ₃c and P ₄d) be positioned on the normal section of circular hole, can obtain the radius measurement of tested circular hole, whole measuring process is simple, quick.The four-sensor definite value built by the embodiment of the present invention compares and measures head, and measuring method high-precisionly can get the radius of tested circular hole.

It will be appreciated by those skilled in the art that accompanying drawing is the schematic diagram of a preferred embodiment, the invention described above embodiment sequence number, just to describing, does not represent the quality of embodiment.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (10)

1. a method for contactless multimetering circular hole internal diameter, is characterized in that, the method for described measurement circular hole internal diameter comprises the following steps:

Build three sensor definite values and compare and measure head;

The measurement optical axis of laser displacement sensor is adjusted, respectively meet first measure before and measure time pre-conditioned;

Tested circular hole is constructed leg-of-mutton circumscribed circle, obtains the radius of tested circular hole according to external Triangle Formula.

2. the method for a kind of contactless multimetering circular hole internal diameter according to claim 1, it is characterized in that, described three sensor definite values compare and measure head and comprise: measuring head bottom surface shaft collar,

Described measuring head bottom surface shaft collar is provided with measuring head axis, described measuring head axis is socketed with angle and range adjustment disk, described angle and range adjustment disk are provided with fixing and adjustment hole, described measuring head axis is provided with three fixing rack for sensor, described fixing rack for sensor is provided with laser displacement sensor, described laser displacement sensor is provided with sensor and fixes and adjusting screw.

3. the method for a kind of contactless multimetering circular hole internal diameter according to claim 2, it is characterized in that, the top of described measuring head axis is provided with shaft adapter in measuring head, in described measuring head, shaft adapter is connected with measuring head connecting link, and described measuring head connecting link is used for being connected with machine tool chief axis; The sidewall of described measuring head axis is provided with data and power lead through hole.

4. the method for a kind of contactless multimetering circular hole internal diameter according to claim 2, is characterized in that, described laser displacement sensor is provided with adjustment disk connecting screw; Described laser displacement sensor is laser triangulation displacement sensor.

5. the method for a kind of contactless multimetering circular hole internal diameter according to claim 1, is characterized in that,

Described first measure before be pre-conditionedly: the measurement optical axis adjusting three laser displacement sensors respectively, makes three to measure optical axises at grade, and three extended lines measuring optical axises meet at a bit, and three are measured optical axises angle is between any two 120 °;

Described first pre-conditionedly when measuring is: three sensor definite values are compared and measured head and be placed in the inner optional position of tested circular hole, adjust three sensor definite values and compare and measure head, making three to measure optical axis is positioned on the normal section of tested circular hole, with the center of circle of tested circular hole for true origin, build X-Y coordinate axis.

6. a method for contactless multimetering circular hole internal diameter, is characterized in that, the method for described measurement circular hole internal diameter comprises the following steps:

Build four-sensor definite value and compare and measure head;

The measurement optical axis of laser displacement sensor is adjusted, respectively meet second measure before and measure time pre-conditioned;

Obtain the radius of tested circular hole.

7. the method for a kind of contactless multimetering circular hole internal diameter according to claim 6, it is characterized in that, described four-sensor definite value compares and measures head and comprises: measuring head bottom surface shaft collar,

Described measuring head bottom surface shaft collar is provided with measuring head axis, described measuring head axis is socketed with angle and range adjustment disk, described angle and range adjustment disk are provided with fixing and adjustment hole, described measuring head axis is provided with four fixing rack for sensor, described fixing rack for sensor is provided with laser displacement sensor, described laser displacement sensor is provided with sensor and fixes and adjusting screw.

8. the method for a kind of contactless multimetering circular hole internal diameter according to claim 7, it is characterized in that, the top of described measuring head axis is provided with shaft adapter in measuring head, in described measuring head, shaft adapter is connected with measuring head connecting link, and described measuring head connecting link is used for being connected with machine tool chief axis; The sidewall of described measuring head axis is provided with data and power lead through hole.

9. the method for a kind of contactless multimetering circular hole internal diameter according to claim 7, is characterized in that, described laser displacement sensor is provided with adjustment disk connecting screw; Described laser displacement sensor is laser triangulation displacement sensor.

10. the method for a kind of contactless multimetering circular hole internal diameter according to claim 6, is characterized in that,

Described second measure before be pre-conditionedly: the measurement optical axis adjusting four laser displacement sensors respectively, four are made to measure optical axis at grade, and four extended lines measuring optical axis meet at a bit, adjacent two are measured optical axis included angle is 90 °, and relative two are measured optical axis point-blank;

Described first pre-conditionedly when measuring is: four-sensor definite value is compared and measured head and be placed in the inner optional position of tested circular hole, adjustment four-sensor definite value compares and measures head, four planes measuring optical axis place are made to be positioned on the normal section of tested circular hole, with the center of circle of tested circular hole for true origin, build X-Y coordinate axis.