CN102944164B - Device and method suitable for measuring sphericity of large-size gas floating ball - Google Patents

Abstract

The invention discloses a device and a method suitable for measuring sphericity of a large-size gas floating ball. The method comprises the following steps of: mounting a self-aligning mechanism, a rotating tool and a micrometer dial in an instrument platform of a uniaxial gas floating table; mounting a gas floating ball on the rotating tool; superposing the center of the gas floating ball and the center of the uniaxial gas floating table through the self-aligning mechanism; adjusting the measuring position of the micrometer dial through the rotating tool; rotating the uniaxial gas floating table, and adjusting the measuring position of the micrometer dial relative to a ball through the rotating tool; and finally, obtaining a sphericity error of the ball according to the measuring data. According to the method, high-precision sphericity error measurement of the large-size gas floating ball can be realized.

Description

Be applicable to sphericity measurement mechanism and the method thereof of large scale air floatation ball

Technical field

The present invention relates to measuring technique, be specifically related to a kind of the sphericity measurement mechanism and the method thereof that are applicable to large scale air floatation ball.

Background technology

The air film that three-axis air-bearing table relies on pressurized air to be formed between air-bearing and bearing seat, simulation stage body is floated, thus realize approximate friction free relative motion condition, with the spacecrafts such as the analog satellite mechanical environment that disturbance torque is very little suffered by outer space.As spacecraft motion simulator, three-axis air-bearing table carries out the performance of Physical Simulation for Satellite Control Systems experimental check system, is the important means in spacecraft development process and method.

The nucleus equipment of three-axis air-bearing table is air-floating ball bearing, the sphericity of air-floating ball bearing is one of its processing and the key technical index be concerned about most in using, for undersized air-floating ball bearing, just can measure with three coordinate machine, country has also put into effect corresponding specifications of surveys, but also immature for the measuring technique of large-sized air-floating ball bearing (S more than Φ 500mm), the measurement range of current three coordinate machine is limited, therefore can not apply conventional three coordinate machine mensuration.And no matter be processing or use, must carry out the detection of sphericity for high-precision ball bearing, therefore the sphericity measurement of large scale air floatation ball has important researching value and application prospect.

Find through searching document, Chinese invention patent application number: 200610125076.2, patent name is " a kind of high-accuracy sphericity pneumatic measuring system ", this invention adopts many gauge heads relative measurement, object measures sphericity and the radius of sphere or ball-and-socket workpiece, but system is complicated, its gauge used can also use for the ball of stock size, but large-sized ball is measured, a design inherently difficult problem for this gauge, its precision is by the restriction of measurement itself in addition, is difficult to reach micron order high precision.

Chinese invention patent application number: 200610118486.4, patent name is: the pick-up unit of sphericity and method thereof, this invention adopts conventional clock gauge to coordinate chord gauge cup to measure sphericity, because high-precision air floatation ball can not allow external touch metering system, and this measurement scheme is difficult to reach high precision, therefore the method is not suitable for the sphericity measurement of high precision air floatation ball.

Jiang Zhuande, Wu Zifang, Yuan Guoying etc. (are published in metering journal at its paper " research of Global Error test macro ", 1996, 17 volumes, 4th phase, the page number: 266-268) in, propose a kind of Global Error detection scheme based on roundness measuring equipment 3 air supporting spheroid dividing apparatus, but because 3 air supporting spheroid dividing apparatus adopt air supporting supported at three point spheroid, and the deadweight of large scale air floatation ball is very large, this device can not meet the detection needs of this kind of large scale air floatation ball, even if air floatation ball will be supported when increasing the strong point also can cause to utter long and high-pitched sounds and cause measuring.

Summary of the invention

The object of the present invention is to provide a kind of sphericity measurement mechanism for large scale air-floating ball bearing and method.

The object of the present invention is achieved like this: one is applicable to large scale air-floating ball bearing sphericity measurement mechanism, it is by single-axle air bearing table (1), core-regulating mechanism (2), rotary tooling (3), dial gauge (4) forms, it is characterized in that: single-axle air bearing table (1) is installed on ground, core-regulating mechanism (2) is placed on the load carrying platform of single-axle air bearing table (1), rotary tooling (3) is arranged on core-regulating mechanism (2), and dial gauge (4) is installed on ground pedestal.

The present invention also has following feature:

Use the large scale air-floating ball bearing sphericity measuring method being applicable to large scale air-floating ball bearing sphericity measurement mechanism as above and realizing, as follows:

Step one: pass to gases at high pressure to single-axle air bearing table and core-regulating mechanism;

Step 2: air-floating ball bearing is installed on rotary tooling;

Step 3: make the center of air-floating ball bearing and the center superposition of single-axle air bearing table by core-regulating mechanism;

Step 4: adjustment dial gauge makes it the equatorial circle of measuring junction in the face of accurate air floatation ball;

Step 5: rotate single-axle air bearing table to 15 ° i position around vertical axes, i=0,1,2...23, dial gauge is measured the distance of its gauge head and sphere and is recorded the reading d of dial gauge ₁(i) (i=0,1,2 ..., 23), in measuring process, the sensitive direction of dial gauge points to the centre of sphere all the time;

Step 6: adjustment rotary tooling makes air floatation ball walk around the horizontal rotational shaft 15 ° of the centre of sphere, is in-15 ° and+15 ° respectively;

Step 7: rotate single-axle air bearing table to 15 ° i position i=0,1,2...23 around vertical axes, dial gauge is measured the distance of its gauge head and sphere and is recorded the reading d of dial gauge _j(i) (j=2,3; I=0,1,2 ..., 23), in measuring process, the sensitive direction of dial gauge points to the centre of sphere all the time;

Step 8: measurement data is processed to the Global Error obtaining ball:

$\begin{array}{c}{\mathrm{\Δd}}_j\left(i\right)=d_j\left(i\right)-{\stackrel{\‾}{d}}_j\left(i\right)-\frac{2}{24}\cos \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\cos \frac{2\mathrm{\πk}}{24}\right)\\ -\frac{2}{24}\sin \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\sin \frac{2\mathrm{\πk}}{24}\right)-x_{2c}\cos \frac{4\mathrm{\πi}}{24}-x_{2s}\sin \frac{4\mathrm{\πi}}{24}\end{array}$

Wherein x _2c, x _2sfor the second harmonic coefficient of air floating table Radial mixing.

The present invention can realize the measurement of spherical errors to large scale air floatation ball, contactless, precision is high, does not produce other influences to air floatation ball.

Accompanying drawing explanation

Fig. 1 is the sphericity measurement mechanism composition schematic diagram of air floatation ball;

Fig. 2 is rotating mechanism schematic diagram in air floatation ball sphericity measurement mechanism;

Embodiment

Below in conjunction with accompanying drawing citing, the invention will be further described.

Embodiment 1:

Composition graphs 1, one of the present invention is applicable to large scale air-floating ball bearing sphericity measurement mechanism, it is by single-axle air bearing table (1) core-regulating mechanism (2), rotary tooling (3), dial gauge (4) forms, it is characterized in that: single-axle air bearing table (1) is installed on ground, core-regulating mechanism (2) is placed on the load carrying platform of single-axle air bearing table (1), rotary tooling (3) is arranged on core-regulating mechanism (2), and dial gauge (4) is installed on ground pedestal.Adopt air floating platform to coordinate micromatic setting and locking device to realize, the design like this based on air floating platform can ensure that the movement of large scale air floatation ball is not only convenient but also accurate.Air floatation ball to be measured is installed on rotary tooling, air floatation ball can be made to rotate to an angle around its centre of sphere by rotary tooling.

Use the large scale air-floating ball bearing sphericity measuring method being applicable to large scale air-floating ball bearing sphericity measurement mechanism as above and realizing, as follows:

Step one: pass to gases at high pressure to single-axle air bearing table and core-regulating mechanism;

Step 2: air-floating ball bearing is installed on rotary tooling;

Step 3: make the center of air-floating ball bearing and the center superposition of single-axle air bearing table by core-regulating mechanism;

Step 4: adjustment dial gauge makes it the equatorial circle of measuring junction in the face of accurate air floatation ball;

Step 5: rotate single-axle air bearing table to 15 ° i position around vertical axes, i=0,1,2...23, dial gauge is measured the distance of its gauge head and sphere and is recorded the reading d of dial gauge ₁(i) (i=0,1,2 ..., 23), in measuring process, the sensitive direction of dial gauge points to the centre of sphere all the time;

Step 6: adjustment rotary tooling makes air floatation ball walk around the horizontal rotational shaft 15 ° of the centre of sphere, is in-15 ° and+15 ° respectively;

Step 7: rotate single-axle air bearing table to 15 ° i position i=0,1,2...23 around vertical axes, dial gauge is measured the distance of its gauge head and sphere and is recorded the reading d of dial gauge _j(i) (j=2,3; I=0,1,2 ..., 23), in measuring process, the sensitive direction of dial gauge points to the centre of sphere all the time;

Step 8: measurement data is processed to the Global Error obtaining ball:

$\begin{array}{c}{\mathrm{\Δd}}_j\left(i\right)=d_j\left(i\right)-{\stackrel{\‾}{d}}_j\left(i\right)-\frac{2}{24}\cos \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\cos \frac{2\mathrm{\πk}}{24}\right)\\ -\frac{2}{24}\sin \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\sin \frac{2\mathrm{\πk}}{24}\right)-x_{2c}\cos \frac{4\mathrm{\πi}}{24}-x_{2s}\sin \frac{4\mathrm{\πi}}{24}\end{array}$

Wherein x _2c, x _2sfor the second harmonic coefficient of air floating table Radial mixing.

Embodiment 2:

Composition graphs 2, the data processing that air-floating ball bearing sphericity of the present invention is measured does following explanation:

Air floatation ball is arranged on rotating mechanism, by the center of core-regulating mechanism by air floatation ball and the center superposition of single-axle air bearing table, with latch mechanism, core-regulating mechanism is locked.Realize air floatation ball by rotating mechanism (as shown in Figure 2) and rotate to a certain warp circle around pole axis, the round degree of warp of air floatation ball is measured with dial gauge, warp circle is great circle, the sensitive direction of dial gauge points to the centre of sphere all the time, the deviation from circular from of different warps circle is in addition comprehensive, just can obtain the Global Error of whole ball.

The gauge head of dial gauge is placed on on air floatation ball centre of sphere sustained height, and turntable can drive whole air floatation ball to rotate, and measures the deviation from circular from of air floatation ball great circle, when air floatation ball is after fulcrum rotates certain angle, can measure again the deviation from circular from of another warp circle.

(1) air floatation ball is turned to respectively-15 °, 0 and 15 °;

(2) rotating table to 15 ° i position, the reading d of record dial gauge _j(i), (j=1,2,3), (i=0,1,2 ..., 23);

(3) data processing:

After each great circle measured deducts average and first harmonic, then deducting the impact of Radial mixing, is exactly the deviation from circular from of this great circle.The reading of dial gauge is

d _x＝s(0，-γ)+e _xcosγ-e _ysinγ+Δx(γ)

Its measuring accuracy depends on the precision of dial gauge and the measuring accuracy of Radial mixing.And Radial mixing mainly second harmonic composition, if certain measures cross section 24 point data d _x(i).(i=0,1,2 ..., 23), note Δ x _2c, Δ x _2sfor the second harmonic coefficient of Radial mixing, then have:

$\begin{array}{c}{\mathrm{\Δd}}_j\left(i\right)=d_j\left(i\right)-{\stackrel{\‾}{d}}_j\left(i\right)-\frac{2}{24}\cos \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\cos \frac{2\mathrm{\πk}}{24}\right)\\ -\frac{2}{24}\sin \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\sin \frac{2\mathrm{\πk}}{24}\right)-x_{2c}\cos \frac{4\mathrm{\πi}}{24}-x_{2s}\sin \frac{4\mathrm{\πi}}{24}\end{array}$

So average in the data that detect of dial gauge and first harmonic are eliminated completely, the second harmonic in the turn error of air floating shaft system also eliminates, the harmonic error of more than three times and three times in data only in remaining Global Error and turn error.

The Simple calculating formula of described invention precision can be obtained in sum: sphericity measuring accuracy=(single-axle air bearing table positional accuracy measurement ²the measuring accuracy of+dial gauge ²) ^0.5.Single-axle air bearing table positional accuracy measurement can reach 0.12 μm, and the measuring accuracy of dial gauge can reach 0.1 μm, and therefore the measurement of spherical errors precision of this method is better than 0.16 μm.

Claims (1)

1. a large scale air-floating ball bearing sphericity measuring method, the measurement mechanism adopted comprises single-axle air bearing table (1), core-regulating mechanism (2), rotary tooling (3) and dial gauge (4), single-axle air bearing table (1) is installed on ground, core-regulating mechanism (2) is placed on the load carrying platform of single-axle air bearing table (1), rotary tooling (3) is arranged on core-regulating mechanism (2), dial gauge (4) is installed on ground pedestal

It is characterized in that, method is as follows:

Step one: pass to gases at high pressure to single-axle air bearing table and core-regulating mechanism;

Step 2: air-floating ball bearing is installed on rotary tooling;

Step 3: make the center of air-floating ball bearing and the center superposition of single-axle air bearing table by core-regulating mechanism;

Step 4: adjustment dial gauge makes it the equatorial circle of measuring junction in the face of accurate air floatation ball;

Step 5: rotate single-axle air bearing table to 15 ° i position around vertical axes, i=0,1,2...23, dial gauge is measured the distance of its gauge head and sphere and is recorded the reading d of dial gauge ₁(i) (i=0,1,2 ..., 23), in measuring process, the sensitive direction of dial gauge points to the centre of sphere all the time;

Step 6: adjustment rotary tooling makes air floatation ball walk around the horizontal rotational shaft 15 ° of the centre of sphere, is in-15 ° and+15 ° respectively;

Step 7: rotate single-axle air bearing table to 15 ° i position i=0,1,2...23 around vertical axes, dial gauge is measured the distance of its gauge head and sphere and is recorded the reading d of dial gauge _j(i) (j=2,3; I=0,1,2 ..., 23), in measuring process, the sensitive direction of dial gauge points to the centre of sphere all the time;

Step 8: measurement data is processed to the Global Error obtaining ball:

$\begin{array}{c}{\mathrm{\Δd}}_j\left(i\right)=d_j\left(i\right)-{\stackrel{\‾}{d}}_j\left(i\right)-\frac{2}{24}\cos \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\cos \frac{2\mathrm{\πk}}{24}\right)\\ -\frac{2}{24}\sin \frac{2\mathrm{\πi}}{24}\underset{k=0}{\overset{23}{\mathrm{\Σ}}}\left(d_j\left(k\right)\sin \frac{2\mathrm{\πk}}{24}\right)-x_{2c}\cos \frac{4\mathrm{\πi}}{24}-x_{2s}\sin \frac{4\mathrm{\πi}}{24}\end{array}$

Wherein x _2c, x _2sfor the second harmonic coefficient of air floating table Radial mixing.