134 results about "Roundness error" patented technology

An online monitoring device for the radial rotation accuracy of a main shaft is disclosed, wherein a monitoring ring is installed at the radial measuring position of the main shaft; three eddy-current displacement sensors are installed on the monitoring ring; the proximitors of the eddy-current displacement sensors are connected with the terminal board of a data acquisition board card; the data acquisition board card is connected to an industrial computer via a PCI (peripheral component interconnection) slot; when the main shaft is in a rotating state, the eddy-current displacement sensors convert the measured voltage signal to a standard voltage signal via the proximitors; the analog signal is converted to a digital signal via a signal conditioning circuit module and an A/D (analog/digital) conversion module on the data acquisition board card, and then the digital signal enters into the industrial computer; the radial displacement signal of the main shaft is obtained by signal acquisition and analysis software; the roundness error of the main shaft is separated out by applying a three-point error separation technology, thereby obtaining the rotation error of the main shaft; and finally the analysis result of the rotation accuracy of the main shaft is displayed. The online monitoring device for the radial rotation accuracy of a main shaft has the advantages of being high in accuracy and convenient in adjustment.

The present invention belongs to the field of precise instrument manufacture and measurement technology, and is especially self-separation method and device for spatial error of super-precise revolution reference. The method of Z-direction section-by-section separation of super-precise revolution reference spatial motion error can meet the requirement of high precision cylindricity instrument to reduce spatial revolution error. The self-separation device for spatial error of super-precise revolution reference is developed by means of integrating roundness error separating system and cylindricity instrument revolution main shaft system. The bench revolving single-transposition small-angle error separation method is adopted in realizing the section-by-section separation of spatial revolution motion error of cylindricity instrument revolution main shaft, so as to reach the aim of reducing the effect of the spatial revolution motion error on measurement result.

The invention discloses a method and device for measuring main shaft rotary errors with the capacity of installation eccentricity separation. The device comprises a displacement sensor installation clamping device, a displacement sensor, a grating encoder, a signal cable, a data processor and a computer. According to the measurement process, measurement is conducted by the displacement sensor according to three selectable modes with three different positions of the external profile of a main shaft serving as sampling starting points, other components, except for first-order harmonic waves, of main shaft roundness errors are obtained on the basis of the three-point method principle, secondary separation is conducted according to the provided algorithm, installation eccentricity is separated from the rotary errors, and therefore a pure rotary movement error value of the main shaft is obtained. On one hand, the roundness errors of the profile of the main shaft and eccentric errors of installation of a standard ball and the sensor are separated from the rotary movement errors of the main shaft, so that the separation operand is small. On the other hand, only one displacement sensor is adopted and measurement errors caused by a sensor performance difference because of three sensors adopted in a common three-point method error separation technology are avoided.

The invention discloses a workpiece axis positioning error compensation method for an axle housing roundness and cylindricity detecting device and belongs to the field of detection. The method is characterized in that an axle housing positioning model is built, a first section, a second section and a third section are arranged on the model, and the second section and the third section are used tocorrect the first section step by step. The method specifically includes: a target section uses O as the benchmark to perform spatial translation on a circle contour where O1 is located, performing axis eccentricity compensation to obtain a section S1 after eccentricity correction, and an axis L and the section S1 are rotated a theta degree along a Z axis to obtain a section S2; the axis L and thesection S2 are rotated an alpha degree along a Y axis to allow the axis L to coincide with the Z axis so as to obtain a section S3; the section S3 and the axis L are reversely rotated theta degrees to obtain the section S4; error evaluation is performed on the section S4 to obtain real roundness errors with workpiece axis positioning eccentricity inclination errors being removed, and a constraintcondition beta is provided. The workpiece axis positioning error compensation method can compensate roundness errors and cylindricity errors caused by workpiece axis positioning eccentricity and workpiece axis positioning inclination, increase axle housing detection precision and meet ultra-precision machining requirements.

The invention relates to a method for online tracking and measuring the roundness error and the machine tool main spindle error. It measures the tracking roundness and the diameter making use of three displacement sensors in the online measuring device, and transforms the time-domain signal is collected when measuring into frequency domain signal then analyses the signal. It separates the roundness error coming from the eccentric rotations from system error online, so achieves online measure of the roundness error and system error and enhances the measurement accuracy.

A method for separating roundness error of single transposition includes selecting proper transposition angle a for carrying out single small angle transposition in relevant angle to rotation major axis and realizing complete harmonic separation of z(n) and g(n) as in scope of 1-100 upr harmonic wave by measuring workpiece error g(n) and major axis transposition error z(n) before and after workpiece transposition as well as utilizing quick. Fourier series transform and harmonic analysis.

The invention relates to a roundness error evaluation method based on a variable-metric chaotic simulated annealing algorithm. The roundness error evaluation method comprises the following steps of: taking the simulated annealing algorithm as optimizing coarse searching first, and then taking the high efficiency of a chaos optimization algorithm as optimizing fine searching to ensure that the optimizing process is concise and efficient. Because the optimizing result of the simulated annealing algorithm is independent of an initial value, an actual globally optimal area is searched by adopting the simulated annealing algorithm, and the chaos optimization algorithm is excellent in execution efficiency and is suitable for carrying out fine searching in the globally optimal area, thereby searching a globally optimal solution, and therefore fewer iterations are obtained in the optimization process; and meanwhile, the chaotic mapping xtin=cos (1/xtin2) provided by the invention can better realize chaotic optimizing, the [a1, i+1, b1, i+1] and [a2, i+1, b2, i+1] are ceaselessly decreased according to the solution space variation in the execution process, and therefore the optimizing process ceaselessly approaches to the globally optimal solution.

The invention discloses a testing and analyzing system for rotating errors of a main shaft. The testing and analyzing system comprises a hardware part and a software part, wherein the hardware part comprises a bracket or magnetic stand, laser displacement sensors, signal connecting wires, a signal adapter plate and a signal acquisition card, wherein the bracket or magnetic stand is fixedly arranged on the main shaft; the laser displacement sensors and the bracket or magnetic stand are connected to acquire axial displacement runout of the main shaft; the signal output end of each laser displacement sensor is connected with the input end of the signal acquisition card through the signal connecting wire and the signal adapter plate; the signal adapter plate is used for outputting more than two laser displacement sensors according to a unified format; a software system is arranged on a computer; the computer communicates with the output end of the signal acquisition card by using testing software, acquires a displacement signal of each laser displacement sensor, then performs analysis processing on a filtering algorithm and a separation algorithm and separates and displays roundness error and rotating error. According to the testing and analyzing system disclosed by the invention, the roundness error and the rotating error of the main shaft can be acquired quickly and accurately; the testing is simple and practical.

The invention relates to a sensor mounting adjustment system and a laser leveling reference device. The sensor mounting adjustment system comprises at least three sensor mounting adjustment devices and a laser leveling reference device for mounting a laser. Each sensor mounting adjustment device is provided with a height adjustment part for adjusting level of a sensor fixing seat and a level alignment mechanism. The level alignment mechanism comprises a target positioning hole arranged on a front mounting plate and a target reticle arranged on a rear mounting plate. The connection line between the target positioning hole and the target reticle is arranged parallelly with the sensor. The laser leveling reference device of the invention is provided with at least three height adjustment parts arranged at intervals around the circumferential direction for adjusting level of the sensor fixing seat. According to the system and the device of the invention, horizontal coplane and concentric mounting of measurement axes of multiple sensors can be quickly realized, efficiency and precision of mounting and positioning of the sensor are improved, and the roundness error measurement precision and the rotation error measurement precision can be further ensured.

The invention relates to a method about diametrical two points and six level measuring roll roundness error and machine tool spindle error., it makes the analysis when time-finite signal collected by two displacement sensors which are set according to diametrical method during six different displacement measuring changes into frequency domain, it makes separation of roundness error of roll which makes eccentric rotatoexercise and spindle motion error, and it realizes measures online about roundness error of roll and spindle motion error, thus, it improves the precision of measuring.

A method and system for computing and displaying a roundness error of an object specifies different colors that respectively represents an error range of points. The method and system receives a point cloud of the object and fits a circle based on the point cloud. The method and system computes an error of each point in the point cloud by computing a distance between the each point and the circle, colorizes the points in the point cloud according to the errors and the specified colors, and generates and outputting a graphic roundness error analysis report.

The invention relates to an improved three-point method for turning error and roundness error measurement. The method includes the following steps that: three displacement sensors are distributed at different angular positions so as to measure the radial run-out of a detection bar, and a high-frequency data acquisition system is utilized to record the measurement results of the sensors, and a three-point error separation technology is utilized to calculate the Fourier coefficients of harmonic waves of roundness error; the second sensor and/or third sensor is re-installed at different angles, the three-point method is repeated to perform measurement for many times, so that each Fourier coefficient can obtain a plurality of estimated values; a Fourier coefficient which is calculated through a transfer matrix of which the determinant is maximum is a most accurate Fourier coefficient estimated value; and the roundness error can be calculated through composite calculation based on the most accurate Fourier coefficient estimated value. With the method of the invention adopted, the accuracy of the estimation of each harmonic wave can be improved, and therefore, the accuracy of whole roundness error measurement can be improved.

The invention disclose a mechanical processing positioning device, which comprises a base (1), an adjusting support assembly and an adjustable clamping mechanism, wherein the adjusting support assembly comprises a cylindrical taper pin (5), a compression spring A (6) and a screw plug (7), the cylindrical taper pin (5) is arranged in an inner cavity (2), the adjustable clamping mechanism comprises an adjusting screw rod (10), a press plate (11) and a compression spring B (12), the press plate (11) and the compression spring B (12) are sheathed outside the adjusting screw rod (10), and the adjusting screw rod (10) penetrates through a through hole (3) arranged on the base (1) and is fixed by a locking screw bolt (16). The mechanical processing positioning device has the beneficial effects that the diameter of the large end of a cone front part (8) is greater than the diameter of a blank hole, the wider positioning range is realized, the cylindrical taper pin (5) is tightly matched with the blank hole by the adjusting support assembly via the extension and retraction of the compression spring A (6), the influence of size and roundness errors of the blank hole can be overcome, the matching clearance is eliminated, and the positioning error is greatly reduced.

The invention belongs to the field of the mechanical processing, in particular to a follow measurement method for roundness of a crankshaft pin, which is characterized in that a measuring head is arranged on a grinding carriage guide rail, and the vertical plane of the measuring head leans tightly against the external surface of the crankshaft pin to be measured; a crankshaft pin specimen is selected, and an on-line measurement roundness error at various angles of the connecting rod journal specimen is measured on line; the actual roundness error is deducted from the measured roundness error of the specimen so as to obtain fixed roundness error of the measuring system; the data about the fixed roundness error are input into the measuring system, the workpieces are arranged, and the actual roundness error of the connecting rod journal workpiece can be obtained by automatically subtracting the fixed roundness error of the workpiece from the measuring roundness error of the workpiece, and the numeral system carries out another machining to eliminate the workpiece roundness error, according to the correction program data of the actual roundness error of the workpiece. The follow measurement method of the invention adopts single-point measurement, thus having the advantages of simple structure, convenient measurement, being scientific and rational and having good economy.

The invention provides a roundness uncertainty evaluation method based on probability density function estimation, and the method comprises the steps: carrying out the roundness sampling of a measuredobject, and obtaining a group of measurement point data; fitting a circle according to the measurement point data, and calculating a roundness error; acquiring a plurality of groups of measurement point data to obtain a plurality of roundness errors, and taking the roundness errors as a group of random variables; establishing a random variable probability density function, a sample origin momentgenerated through random variable calculation replacing a theoretical origin moment for mathematical change, and constructing constraint conditions of probability density; taking the origin moment ofthe sample as a condition, taking a probability density constraint condition as an objective function, and obtaining a probability density function of the roundness error; and performing numerical integration on the probability density function to calculate the standard deviation of the probability density so as to realize uncertainty evaluation of roundness measurement. The roundness error measurement uncertainty evaluation method can realize roundness error measurement uncertainty evaluation of small samples, and has the characteristics of fast algorithm convergence and stable calculation numerical value.

The invention provides a rotary part arc trimming algorithm. The rotary part arc trimming algorithm is characterized by comprising the steps that parameters are initialized; roundness measurement is carried out; a roundness error is evaluated; angular speeds of trimming joints are determined; the motor rotating speed control pulse number which should be input for controlling the motor rotation is obtained, an indexing angle alpha is converted into a control angle of the motor, and then the control angle of the motor is converted into a corresponding motor angle control pulse number; and the motor controls a trimming tool to complete trimming of a workpiece to be trimmed according to the motor rotating speed control pulse number and the motor angle control pulse number. According to the other technical scheme, the invention provides a rotary part arc trimming control system using the rotary part arc trimming algorithm. According to the invention, on the premise that rotary part arc trimming cost is reduced, the roundness error can be rapidly converged; and the rotary part arc trimming algorithm and the rotary part arc trimming control system have the beneficial effects of being low in cost, high in efficiency and intelligentized.

The invention discloses a method for separating and handling the thermal error, roundness error and turning error of a main shaft of a machine tool. The method comprises the steps of circumferentially uniformly distributing four temperature sensors and four electrical vortex sensors in the radial direction of the main shaft; setting the sampling time of the sensors according to the rotating speed of the main shaft, and acquiring the temperature and radial displacement signals of the main shaft of the machine tool; performing equivalent-cycle truncation for the radial displacement signals of the main shaft, and then carrying out differentiating to obtain the radial thermal displacement error of the main shaft, building a thermal error model through a least-square method, and then separating out the thermal error from the radial displacement error; performing weighted summation for the radial displacement signals of the main shaft, acquired by the four electric vortex sensors, so as to build a function relational expression, and then separating out the roundness error of the main shaft through discrete Fourier transform; subtracting the roundness error and the thermal error from the measured data, so as to separate out the turning error of the main shaft. The method achieves the separating of the radial thermal error, the roundness error and the turning error of the main shaft of the machine tool. Compared with the common three-point error separating method, the method has the advantage that the separating precision is improved.

The invention relates to a method for carrying out diameter two-point six-transposition measurement on a roundness error of a large-scale shaft part and a kinematic error of a machine tool spindle. According to the method, a time domain signal acquired in the measuring process of six different transpositions according to two displacement sensors which are diametrically arranged is transformed into a frequency domain to be analyzed, and the roundness error of the large-scale shaft part which takes the eccentric rotating motion is separated from the kinematic error of the spindle by a machine, so that the on-line measurement of the roundness error of the large-scale shaft part and the motion of the spindle is realized and the measurement accuracy is improved.

The invention relates to a bar centerless grinding technology and a special knife board adjusting device thereof; the bar centerless grinding technology comprises the following steps of: firstly carrying out rough machining on a bar so as to enable the workpiece allowance to be between 0.3mm and 0.5mm, the roundness error is below 0.10mm and the straightness accuracy is within 1mm/m; the bar centerless grinding technology and the special knife board adjusting device thereof disclosed by the invention can efficiently eliminate or reduce the original roundness error of a bar blank, thereby controlling the roundness error of a workpiece finished product, improving the product percent of pass and saving the production cost; the whole process flow is simple in process and easy to operate; and the special knife board adjusting device is simple in structure, and convenient to debug and maintain.

The invention discloses a roundness error evaluating method based on EMD. The method comprises performing angle sampling on a workpiece within one circle to obtain radius data of the workpiece, performing EMD on the radius data to decompose the radius data into a plurality of intrinsic mode functions (IMF) and a residual component from high frequency to low frequency, removing interference signal components through wave numbers; performing reconstitution through residue IMF to obtain surface shape error signals and further to calculate roundness errors. The roundness error evaluating method based on EMD is high in anti-interference performance, self-adapting, higher in analysis precision compared with traditional methods, rapid and convenient in the entire analysis process and easy to master by users.