CN104034462A - Digital non-contact type torque measurement method - Google Patents

Abstract

The invention discloses a kind of digital non-contact torque measuring methods. Contact torque measuring method is poor for applicability for the detection of dynamic torque, and phase type and magnetoelasticity formula torque measuring method detection algorithm are more complicated. The specific steps of the present invention are as follows: N reflective strip being uniformly attached on the periphery of tested rotary shaft, every reflective strip is along the axial arrangement for being tested rotary shaft; Laser emission item and laser pick-off item are arranged in the top of tested rotary shaft; Torque is applied to tested rotary shaft, Laser emission item emits laser point, and laser pick-off item detects the laser points of reflective strip reflection ; When tested rotary shaft generates deformation, reflective strip also produces angle therewith and is Variation; Acquire the angle of reflective strip Yu Laser emission item , by , obtain the torsion angle in tested rotating shaft terminal face , it is tested torque suffered by rotary shaft . The present invention realizes quick, the dynamic detection to high-speed rotating shaft torque.

Description

A kind of digital non-contact torque measuring method

Technical field

The invention belongs to sensor technical field, relate to torque measuring method, be specifically related to a kind of digital non-contact torque measuring method.

Background technology

In rotating machinery, the torque that turning axle bears is related to safety and the system works efficiency of whole system, so torque of rotating shaft is detected and is absolutely necessary in Practical Project.And now plant equipment towards future development rapidly and efficiently, so the moment of torsion detection of dynamic of high-speed rotating shaft more and more comes into one's own.

The method that moment of torsion detects at present has several as follows: 1, strain bridge-type, thus it is to utilize electric-resistance strain ga(u)ge to detect the big or small torque value that obtains of strain of axle; 2, phase type, it is that while being subject to moment of torsion by detection axle, the phase differential of two disks detects moment of torsion; 3, magnetoelasticity formula, it is to have utilized the reverse magnetostrictive effect of ferromagnetic material and some other alloy to detect moment of torsion.The shortcoming of method 1: because the detection of this method need to be installed foil gauge and be arranged cabling, institute thinks the measuring method of contact, poor for applicability for dynamic moment of torsion detection.Method 2 and 3 shortcoming: although these two kinds of measuring methods are all contactless measurements, due to more complicated on detection algorithm, and the data of method 3 outputs are analog quantity, and follow-up data processing is loaded down with trivial details.

If can realize the moment of torsion detection of dynamic of high-speed rotating shaft, and only need simply process detecting data, this is undoubtedly a kind of more satisfactory mode.Therefore design a kind of noncontact, and the contactless torque measuring method of digital data output just seems very necessary.

Summary of the invention

The object of the invention is for the deficiencies in the prior art, a kind of digital non-contact torque measuring method is provided, realize the moment of torsion detection of dynamic to high-speed rotating shaft, detect rapidly the dynamic torque of high-speed rotating shaft.

Concrete steps of the present invention are as follows:

Step 1, by the uniform periphery that is attached to tested turning axle of N bar reflecting strips, every reflecting strips is axial arranged along tested turning axle; N is integer, and span is 4～8.

The width of described reflecting strips is D, and length is L; D=0.01～0.2r, the periphery radius that r is tested turning axle; The length L of described reflecting strips is less than or equal to the length of tested turning axle.

Step 2, laser transmitting-receiving device is arranged on to the top of tested turning axle.

Described laser transmitting-receiving device comprises Laser emission bar and laser pick-off bar, and described Laser emission bar is all parallel with reflecting strips with laser pick-off bar; The length of Laser emission bar and laser pick-off bar is equal in length with reflecting strips all; Described Laser emission bar is provided with n the laser beam emitting head being equally spaced, and n is integer, and span is 800～1200; Spacing l=0.l～the 0.2mm of adjacent two laser beam emitting heads; Described laser pick-off bar is provided with n the laser pickoff being equally spaced, and each laser pickoff position is corresponding with a laser beam emitting head.

Step 3, tested turning axle is applied to moment of torsion, Laser emission bar Emission Lasers point, the laser that laser pick-off bar the detects reflecting strips reflection n that counts _r.When tested turning axle produces deformation, reflecting strips has also produced the variation that angle is γ thereupon, and the angle of reflecting strips and Laser emission bar is γ ', by geometric relationship, is obtained parameter ab=l * n wherein _rmax, n _rmaxthe laser that revolves reflecting strips reflection while turning around for the tested turning axle maximal value of counting; Can obtain ${\mathrm{\γ}}^{\′}={\tan }^{-1}\left(\frac{D}{l\×n_{r\max }}\right).$

Step 4, by geometric relationship, obtain γ=γ ', by mechanical relationship formula, obtained the torsion angle of tested rotating shaft terminal face by moment of torsion formula, can obtain the suffered moment of torsion of tested turning axle periphery diameter d=the 2r of tested turning axle wherein, G is modulus of shearing.

Beneficial effect of the present invention:

The present invention is for the detection of high-speed rotating shaft moment of torsion, at Data processing, sensor is maximal value as long as the laser reflecting in output rotating shaft rotation one-period is counted, then this round values substitution geometric relationship formula and mechanics formula just can be drawn to the torque value of required detection fast, and not need to carry out any digital-to-analog conversion.The present invention can realize quick, the detection of dynamic to high-speed rotating shaft moment of torsion, and the moment of torsion that is applicable to high-speed machine tool main shaft detects.

Accompanying drawing explanation

Fig. 1 is principle of work schematic diagram of the present invention;

To be the present invention be not subject to beat under torque condition the laser spots schematic diagram in reflecting strips at tested turning axle to Fig. 2;

To be the present invention be subject to beat under torque condition the laser spots schematic diagram in reflecting strips at tested turning axle to Fig. 3;

Fig. 4-1st, a schematic diagram when reflecting strips of the present invention does not start to reflect laser spots in tested turning axle rotary course;

Fig. 4-2nd, the schematic diagram that a reflecting strips of the present invention reflects laser in tested turning axle rotary course while counting as maximal value;

Fig. 4-3rd, a schematic diagram when reflecting strips of the present invention finishes reflection laser spots in tested turning axle rotary course.

In figure: 1, laser transmitting-receiving device, 2, tested turning axle, 3, reflecting strips, 4, laser spots.

Embodiment

Below in conjunction with drawings and Examples, the invention will be further described.

A digital non-contact torque measuring method, concrete steps are as follows:

Step 1, as illustrated in fig. 1 and 2, by the uniform periphery that is attached to tested turning axle 2 of six reflecting strips 3, every reflecting strips is axial arranged along tested turning axle 2; Reflecting strips is for swashing reflection of light.

Width D=the 1mm of reflecting strips 3, length L=100mm; Periphery radius r=the 100mm of tested turning axle, because D is much smaller than r, so every reflecting strips can be regarded as plane approx, this measurement that is moment of torsion provides foundation.The length of tested turning axle equals the length L of reflecting strips.

Step 2, as illustrated in fig. 1 and 2, is arranged on tested turning axle 2 tops by laser transmitting-receiving device 1.

Laser transmitting-receiving device 1 comprises Laser emission bar and laser pick-off bar, and Laser emission bar is all parallel with reflecting strips with laser pick-off bar.The length of Laser emission bar and laser pick-off bar is L; Laser emission bar is provided with n the laser beam emitting head being equally spaced, n=1000; The spacing l=0.lmm of adjacent two laser beam emitting heads; Laser pick-off bar is provided with n the laser pickoff being equally spaced, and each laser pickoff position is corresponding with a laser beam emitting head.

Step 3, as shown in Figure 3, applies moment of torsion to tested turning axle 2, Laser emission bar Emission Lasers point 4, the laser that laser pick-off bar the detects reflecting strips 3 reflections n that counts _r.As shown in Figure 2, when moment of torsion is 0, because reflecting strips is completely parallel with Laser emission bar, so in the process of tested turning axle 2 rotations, the laser that laser pick-off bar the detects reflection n that counts _r=n.When tested turning axle produces deformation, reflecting strips has also produced the variation that angle is γ thereupon, and now the angle of reflecting strips and Laser emission bar is γ ', by geometric relationship, is obtained parameter ab=l * n wherein _rmax.The material of tested turning axle is alloy steel, due to tested turning axle High Rotation Speed, as shown in Fig. 4-1,4-2 and 4-3, the sense of rotation that the direction of arrow is tested turning axle, so recording the laser of the reflection cycle of counting into, laser pick-off bar changes the laser reflecting in each cycle maximal value n that counts _rmax=100, can obtain ${\mathrm{\γ}}^{\′}={\tan }^{-1}\left(\frac{D}{l\×n_{r\max }}\right)=5.7.$

Step 4, as shown in Figure 3, obtains γ=γ '=5.7 by geometric relationship, is obtained the torsion angle of tested rotating shaft terminal face by mechanical relationship formula by moment of torsion formula, can obtain the suffered moment of torsion of tested turning axle periphery diameter d=the 2r of tested turning axle wherein, shear modulus G=79.2 * 10 ⁹pa.

Claims (1)

1. a digital non-contact torque measuring method, is characterized in that: the concrete steps of the method are as follows:

Step 1, by the uniform periphery that is attached to tested turning axle of N bar reflecting strips, every reflecting strips is axial arranged along tested turning axle; N is integer, and span is 4～8;

The width of described reflecting strips is D, and length is L; D=0.01～0.2r, the periphery radius that r is tested turning axle; The length L of described reflecting strips is less than or equal to the length of tested turning axle;

Step 2, laser transmitting-receiving device is arranged on to the top of tested turning axle;

Described laser transmitting-receiving device comprises Laser emission bar and laser pick-off bar, and described Laser emission bar is all parallel with reflecting strips with laser pick-off bar; The length of Laser emission bar and laser pick-off bar is equal in length with reflecting strips all; Described Laser emission bar is provided with n the laser beam emitting head being equally spaced, and n is integer, and span is 800～1200; Spacing l=0.l～the 0.2mm of adjacent two laser beam emitting heads; Described laser pick-off bar is provided with n the laser pickoff being equally spaced, and each laser pickoff position is corresponding with a laser beam emitting head;

Step 3, tested turning axle is applied to moment of torsion, Laser emission bar Emission Lasers point, the laser that laser pick-off bar the detects reflecting strips reflection n that counts _r; When tested turning axle produces deformation, reflecting strips has also produced the variation that angle is γ thereupon, and now the angle of reflecting strips and Laser emission bar is γ ', by geometric relationship, is obtained parameter ab=l * n wherein _rmax, n _rmaxthe laser that revolves reflecting strips reflection while turning around for the tested turning axle maximal value of counting; Can obtain

Step 4, by geometric relationship, obtain γ=γ ', by mechanical relationship formula, obtained the torsion angle of tested rotating shaft terminal face by moment of torsion formula, can obtain the suffered moment of torsion of tested turning axle periphery diameter d=the 2r of tested turning axle wherein, G is modulus of shearing.