CN104990490A - Vehicle pipe part geometric tolerance detection device and method - Google Patents

Abstract

The invention relates to the technical field of mechanical processing detection and discloses a vehicle pipe part geometric tolerance detection device. The vehicle pipe part geometric tolerance detection device comprises a fixing clamp, a plurality of displacement sensors and a microcomputer; and the fixing clamp is used to fix a pipe part, the displacement sensors are respectively disposed at a plurality of positions of the pipe part, the displacement sensors are connected with the microcomputer through a sub wire concentrator, a main wire concentrator and a COM serial port, and the microcomputer calculates a geometric tolerance value of the pipe part at the position according to displacement amounts of the displacement sensors. The invention further discloses a detection method for a geometric tolerance. Detection of the location degree, detection of the roundness degree, detection of flatness degree, detection of coaxiality and detection of other indexes are rapidly completed in clamping one time, detection equipment has a low requirement for environment, and the vehicle pipe part geometric tolerance detection device can be used on a workshop production line in a manner that the vehicle pipe part geometric tolerance detection device is connected through a line.

Description

Automobile-used pipe part form and position tolerance pick-up unit and method

Technical field

The present invention relates to electromechanical integration machining detection technique field, particularly a kind of automobile-used pipe part form and position tolerance pick-up unit and detection method.

Background technology

Along with the development of auto industry proposes more and more higher requirement to the crudy of auxiliary products, the large multiplex drift mode of original whole inspection equipment is carried out, and for the pipe part that rigidity is undesirable, this method is not ideal, easily misjudges.And some index (as flatness, circularity, right alignment etc.) is because testing tool is to the requirement of environment, or the factor such as too time-consuming during test, and cannot synchronously with production on the streamline of production scene detect.Often can only to inspect form by random samples, at test in laboratory.But increasing producer wishes these indexs also entirely to examine.

Automobile pipe part due to the singularity of its requirement on machining accuracy, its position degree sensing range comparatively large (about 1-3 millimeter), and circularity, flatness and right alignment detect franchise and be about 0.1-0.3 millimeter, but the position error of detection faces is larger.

Prior art adopts traditional detection fixture to detect, and position degree adopts mechanical constraint (as drift) and visual method, and circularity, flatness and right alignment adopt sampling observation, and in laboratory, high-precision mechanical scanning mode detects.

Traditional location degree detects and adopts drift mode, low precision, and has misjudgment phenomenon.And though Traditional movement sensors precision is high, sensing range is little, only has hundreds of micron, cannot be used for the position degree detection that variable quantity is 0-3 millimeter scope.

Circularity, flatness and right alignment checkout equipment precision are high, detection spended time is long, high to environmental requirement, therefore, are not suitable for and detect in workshop and production line line.Usually can only inspect by random samples in the past.But increasing user will examine entirely to the technical indicator that drawing marks, and conventional detection devices can not meet the requirement of user.

Summary of the invention

The object of the invention is to solve the problems of the technologies described above, a kind of automobile-used pipe part form and position tolerance pick-up unit and detection method are provided, can be used in the quick detection to pipe part on production line, and reach accuracy of detection requirement.

The technical scheme that the present invention takes is:

A kind of automobile-used pipe part form and position tolerance pick-up unit, it is characterized in that, comprise stationary fixture, multiple displacement transducer and microcomputer, described stationary fixture is used for fixing described pipe part, described multiple displacement transducer is separately positioned on multiple positions of described pipe part, institute's displacement sensors is connected with described microcomputer with COM serial port by a point hub, primary hub, and described microcomputer goes out the form and position tolerance value of described this position of pipe part according to the displacement calculation of multiple displacement transducer.

Further, described pick-up unit also comprises marking machine, and the pipe part detected marks by described marking machine.

Further, institute's displacement sensors is digital capacitive displacement transducer, and the sensing range of institute's displacement sensors is 0-10mm.

Further, the accuracy value of institute's displacement sensors is less than 0.015mm.

Further, described form and position tolerance is Tolerance of Degree of position, and institute's displacement sensors is two, is separately positioned on two mutually perpendicular directions detecting position.

Further, described form and position tolerance is flatness tolerance, and described sensor is 4 to 8, is arranged on the end face of described pipe part, and wantonly three sensors are not on the same line.

Further, described form and position tolerance is roundness tolerance, and described sensor is 4, is separately positioned on the two ends of orthogonal two diameters of described pipe part.

Further, described form and position tolerance is concentricity tolerance, and described sensor is 3, is separately positioned on the tube wall in the same cross section of described pipe part, 3 sensors be 120 degree uniform.

Utilize pick-up unit to carry out a detection method for Tolerance of Degree of position to pipe part, it is characterized in that, comprise the steps:

(1) at each check point of described pipe part, two displacement transducers are set by vertical direction;

(2) the one group of coordinate figure detected is sent to microcomputer by institute's displacement sensors;

(3) described one group of coordinate figure is added that the pipe radius of pipe part obtains Tolerance of Degree of position value by described microcomputer.

Utilize pick-up unit to carry out a detection method for flatness tolerance to pipe part, it is characterized in that, comprise the steps:

(1) arrange multiple displacement transducer at the detection end face of described pipe part, displacement transducer is vertically arranged on end face;

(2) shift value of detection is sent to microcomputer by described multiple displacement transducer;

(3) maximal value of the shift value received is deducted minimum value and obtains flatness tolerance value by described microcomputer.

Utilize pick-up unit to carry out a detection method for roundness tolerance to pipe part, it is characterized in that, comprise the steps:

(1) 2 displacement transducers are respectively set at the two ends of orthogonal two diameters of described pipe part;

The shift value of detection is sent to microcomputer by (2) 4 displacement transducers;

(3) shift value received is calculated two diameter values by described microcomputer, major diameter value is deducted minor diameter value and obtains roundness tolerance value.

Utilize pick-up unit to carry out a detection method for roundness tolerance to pipe part, it is characterized in that, comprise the steps:

(1) tube wall in the same cross section of described pipe part uniformly arranges 3 displacement transducers in 120 degree;

The shift value of detection is sent to microcomputer by (2) 3 displacement transducers;

(3) described microcomputer goes out concentricity tolerance value Δ according to following formulae discovery _t:

${\mathrm{\Δ}}_t=\sqrt{{\mathrm{\ΔX}}^2+{\mathrm{\ΔY}}^2}$

Δ R in formula ₁, Δ R ₂with Δ R ₃be respectively the displacement that 3 displacement transducers detect.

The invention has the beneficial effects as follows:

(1) detection of the index such as position degree, circularity, flatness, right alignment, completes fast under clamped one time;

(2) checkout equipment is low to environmental requirement, can use by line on shop production line;

(3) detection of automobile pipe part can be met, position degree sensing range comparatively large (about 1-3 millimeter), and circularity, flatness and right alignment detection franchise is about 0.1-0.3 millimeter;

(4) detect data can preserve, so that quality assurance services such as the tracking in product later stage;

(5) boost productivity, stop undetected;

(6) detection accuracy is improved, the man-made fault of the erroneous judgement that will occur when avoiding manual detection;

(7) adopt wide-measuring range, high-precision digital sensor, avoids, and the little measurement range of traditional sensors high precision cannot realize the isoparametric electrical measurement of position degree of pipe part.

Accompanying drawing explanation

Accompanying drawing 1 is the layout schematic diagram of sensor on pipe part;

Accompanying drawing 2 is system electrical theory diagram;

Accompanying drawing 3 is the detail view of sensor arrangenent diagram;

Accompanying drawing 4 is flatness principle schematic;

Accompanying drawing 5 is that schematic diagram arranged by the sensor of rhombus end face;

Accompanying drawing 6 is roundness measurement schematic diagram;

Accompanying drawing 7 is right alignment Cleaning Principle and sensor arrangenent diagram;

Accompanying drawing 8 is right alignment Cleaning Principle figure;

Accompanying drawing 9 is the control circuit for electromagnet figure of marking machine;

Accompanying drawing 10 is the cylinder control principle drawing of marking machine;

Accompanying drawing 11 is pick-up unit electrical hardware systematic schematic diagram.

Embodiment

Elaborate below in conjunction with the embodiment of accompanying drawing to the present invention's automobile-used pipe part form and position tolerance pick-up unit and detection method.

Pick-up unit is made up of mechanical mechanism and electric part, and mechanical mechanism comprises the parts such as fixture, marking mechanism, sensor stand and forms.Electrical hardware is made up of components and parts such as industrial microcomputer, digital displacement sensor, hub, communication interface and power supplys.

In mechanical mechanism, fixture is used for fixing tubing measured piece, makes measured piece take correct detection position, and in testing process, keeps this position.Sensor stand is used for fixing displacement transducer, making the holding frame of sensor be in zero-bit when detecting, this zero-bit can be kept in survey process constant.

Zero-bit mentioned here refers to: when detecting zero error exemplar, sensor reading is the ideal position of zero just.Be master body is placed on three-coordinates measuring machine to survey one time during actual use, measure actual error everywhere, and record.Then, exemplar is placed on this fixture, regulates each point sensing station, make its reading equal with actual error.

Represent a displacement transducer see the arrow of in accompanying drawing 1, figure, position degree detects each some layout two sensors, detects two coordinates respectively, as: the coordinate detecting X and Y-axis.Detect the coordinate of section of a pipe, can respectively arrange two sensors at pipe two ends, as: detect X1, Y1 and X2, Y2 coordinate respectively.

Detection plane degree can arrange the sensor of more than four, as P1, P2, P3 and P4 etc.And by the measuring points placement of these sensors in same ideal plane, so-called ideal plane refers to that error is the measured surface plane of zero.

Detect circularity and four sensors R1, R2, R3 and R4 can be set, detect two mutually perpendicular diameters in measured section respectively.A diameter needs two sensors, amounts to needs four sensors.

Detect right alignment and can arrange three sensors, e.g., T1, T2 and T3, three are distributed on around measured section, can determine the principle of a circle with 3, detect the center of circle of measured section with three sensors.

See accompanying drawing 2, the microcomputer of electric control system is connected with primary hub, point hub and digital sensor by COM serial port.Detect and use digital capacitive displacement transducer, this sensor accuracy of detection is high, and sensing range is large, but digital, be furnished with display device and just can observe measured value.Adopt position degree to detect in example and adopt SH-141, its accuracy of detection is not less than 0.015 millimeter in global extent, sensing range 0-10 millimeter.Flatness, circularity and right alignment adopt SH-341, and its accuracy of detection is not less than 0.004 millimeter in global extent, sensing range 0-10 millimeter.Primary hub model is SH-421, point line concentration type number is SH-411, and order wire all adopts RS232.

Respectively each form and position tolerance measuring method is described in detail below.

See accompanying drawing 3, position degree detects that implementation method is as follows, and the position degree in any point has X, Y and Z tri-coordinates in principle, but the radial coordinate of generally sensor measurement xsect.In figure be one three sections pipe its end points and inflection point be A, B, C and D respectively, three sections are called La, Lb and Lc.

Detection two tube section central coordinate of circle are needed for each section of tube core line position, and each center of circle needs two coordinates detecting two axles.As the center of circle, cross section X1 and Z1 two sensors of A end, detect X-axis and the Z axis coordinate figure in this center of circle respectively, because the formal center of circle cannot be detected, therefore, change detector tube outer wall into, then add pipe radius.Here have ignored pipe radius size error and shape error, because these errors are all in a small amount for other position error of grade.X-axis and the Z axis coordinate in the La pipe B end cross section of Lb straight-line segment (strictly the say be) center of circle is detected respectively with X2 and Z2 two sensors.

For the position of Lb end, same selection two cross sections, place four sensors X 3, Z3, X4 and Z4, respectively the home position X-axis at these end pipe two ends and the coordinate of Z axis.

Two cross sections are selected equally for Lc section, if four sensors X 6, Z6, X7 and Z7, detects X-axis and the Z axis coordinate at this section of pipe two ends respectively.

See accompanying drawing 4, it is as follows that flatness detects implementation method, and flatness Cleaning Principle is fairly simple, is provided with N number of check point Δ ₁, Δ ₂Δ _n, each sensor vertical in detection surface, e.g., the zero point of each sensor all in the ideal plane of zero error, then flatness error W _flatness:

W _flatness=(Δ _max-Δ _min)

${\mathrm{\Δ}}_{max}=\underset{1\≤j\≤N}{Max}\left\{{\mathrm{\Δ}}_j\right\}$

${\mathrm{\Δ}}_{min}=\underset{1\≤j\≤N}{Min}\left\{{\mathrm{\Δ}}_j\right\}$

Sensors A 1, A2 ... A5 is distributed in plane and does not expect a little not collinear, and each sensor vertical is in measured surface, and the difference of its maxima and minima can as flatness error, and this method is applicable to the plane of grinding or Milling Machining is formed.

See accompanying drawing 5, because end face in actual production adopts milling or mill to be processed to form, face area is also little, therefore, have employed four sensors distributed close to rhombus four angle modes and detects, A1, A2, A3 and A4 in figure, four represented points in example.

See accompanying drawing 6, roundness measurement implementation method is as follows, the basic main cause of pipe part deviation from circular from is caused to be the distortion that the swan-neck period of the day from 11 p.m. to 1 a.m causes, therefore, two mutually orthogonal calibers can be detected, the direction (shown in Fig. 7) that general layout is consistent with bending direction, deviation from circular from available size diameter difference Δ=(D _max-D _min) be its deviation from circular from.Four sensors record Δ respectively ₁, Δ ₃, Δ ₂and Δ ₄.Then deviation from circular from W _circularity:

W _circularity=| D _max-D _min|=| (Δ ₁+ Δ ₃) – (Δ ₂+ Δ ₄) |.

In example, detect the circularity (D see Fig. 3 holds) of D end, arrange four displacement transducers X7, Z7, X8 and Z8, detect two mutually perpendicular diameter difference respectively.Wherein X7 and Z7 detects with above-mentioned position degree the sensor shared.

See accompanying drawing 7, right alignment detect implementation method as follows, coaxiality error, be exactly in principle detection two sections of pipes center line between bias, but for the pipe part of automobile, normally detect the position deviation between the endoporus and the center line of pipe outer wall of tube end.Heart line for endoporus is difficult to detect, and therefore, take internal taper hole as benchmark, in figure, 1 is taper setting element, and 2 is measured tubes, clamping behind pipe location, sensors A 1, A2 and A3 tri-sensor locations are in same cutting plane, and the angle between two sensors is 120 °.

See accompanying drawing 8, if the radius increment that three sensors record measured tube outer wall is respectively Δ R1, Δ R2 and Δ R3.Then coaxiality error Δ t can be represented by the formula:

${\mathrm{\Δ}}_t=\sqrt{{\mathrm{\ΔX}}^2+{\mathrm{\ΔY}}^2}$

In instantiation, see R1, R2 and R3 tri-sensors of LC section in accompanying drawing 3, between two adjacent sensors, become 120 degree of angles.It detects this outer wall holds endoporus right alignment to D, and now, D end endoporus must be the pilot hole of this measured tube.

See accompanying drawing 9,10, pick-up unit is also furnished with marking mechanism and marks specification product, and the effect of marking mechanism is after having detected, and specification product in this way, then mark.Its effect be prevent undetected.Marking machine is made up of cylinder and marking pen etc., after microcomputer is by inspection, judgement, thinks qualified product, and just by I/O interface, export D1 low level, D2 is high level, and relay J 1 obtains electric, and electromagnet 1DT obtains electric.And relay J 2 dead electricity, 2DT is dead electricity also.Now, three-position valve moves, left side logical validity, and cylinder moves right, and promotes marking pen, measured tube does the mark representing " qualified ".Then, microcomputer exports D2 high level, and D1 is low level.J1 dead electricity, J2 obtain electric, so electromagnet 1DT dead electricity, 2DT obtains electric, and logical validity on the right of three-position valve, marking pen returns original place with cylinder.

In actual applications, the electrical hardware of pick-up unit is made up of components and parts such as industrial microcomputer, digital displacement sensor, hub and connections.

Industrial microcomputer is the core of hardware, and it is by interface connecting sensor, marking machine, and the hardware such as interactive display screen and keyboard, runs TT&C software, completes the work such as detection, computing, judgement.

Digital displacement sensor detected the location variation of each check point of measured piece originally, then, sent measured data by hub, order wire to industrial microcomputer.

See accompanying drawing 11, industrial microcomputer is connected with primary hub with RS232 order wire by the COM1 serial ports of self, primary hub is by RS232 order wire and one to eight (having used six in example) point hub, and each point of hub is connected with one to eight sensor by RSR232 order wire.Therefore, this system serial ports can form a minimum displacement transducer, can reach at most the detection system of 64 displacement transducers.41 sensors are adopted in example.Wherein 10 X-coordinate, 10 Y-coordinate, 10 Z coordinates, 4 for circularity, 4 for flatness, 3 are detected for right alignment.

Microcomputer by the output interface D1 of I/O and D2 pilot relay J1 and J2, J1 and J2 control again the magnet coil of the three-position four-way valve of marking machine movement electric or dead electricity, the movement of solenoid control cylinder, cylinder moves and promotes marking pen and carry out stamped mark.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (12)

1. an automobile-used pipe part form and position tolerance pick-up unit, it is characterized in that: comprise stationary fixture, multiple displacement transducer and microcomputer, described stationary fixture is used for fixing described pipe part, described multiple displacement transducer is separately positioned on multiple positions of described pipe part, institute's displacement sensors is connected with described microcomputer with COM serial port by a point hub, primary hub, and described microcomputer goes out the form and position tolerance value of described this position of pipe part according to the displacement calculation of multiple displacement transducer.

2. automobile-used pipe part form and position tolerance pick-up unit according to claim 1, it is characterized in that: described pick-up unit also comprises marking machine, the pipe part detected marks by described marking machine.

3. automobile-used pipe part form and position tolerance pick-up unit according to claim 1, is characterized in that: institute's displacement sensors is digital capacitive displacement transducer, and the sensing range of institute's displacement sensors is 0-10mm.

4. automobile-used pipe part form and position tolerance pick-up unit according to claim 3, is characterized in that: the accuracy value of institute's displacement sensors is less than 0.015mm.

5. automobile-used pipe part form and position tolerance pick-up unit according to any one of claim 1 to 4, it is characterized in that: described form and position tolerance is Tolerance of Degree of position, institute's displacement sensors is two, is separately positioned on two mutually perpendicular directions detecting position.

6. automobile-used pipe part form and position tolerance pick-up unit according to any one of claim 1 to 4, it is characterized in that: described form and position tolerance is flatness tolerance, described sensor is 4 to 8, is arranged on the end face of described pipe part, and wantonly three sensors are not on the same line.

7. automobile-used pipe part form and position tolerance pick-up unit according to any one of claim 1 to 4, it is characterized in that: described form and position tolerance is roundness tolerance, described sensor is 4, is separately positioned on the two ends of orthogonal two diameters of described pipe part.

8. automobile-used pipe part form and position tolerance pick-up unit according to any one of claim 1 to 4, it is characterized in that: described form and position tolerance is concentricity tolerance, described sensor is 3, is separately positioned on the tube wall in the same cross section of described pipe part, 3 sensors be 120 degree uniform.

9. utilize pick-up unit as claimed in claim 5 to carry out a detection method for Tolerance of Degree of position to pipe part, it is characterized in that: comprise the steps:

(1) at each check point of described pipe part, two displacement transducers are set by vertical direction;

(2) the one group of coordinate figure detected is sent to microcomputer by institute's displacement sensors;

(3) described one group of coordinate figure is added that the pipe radius of pipe part obtains Tolerance of Degree of position value by described microcomputer.

10. utilize pick-up unit as claimed in claim 6 to carry out a detection method for flatness tolerance to pipe part, it is characterized in that: comprise the steps:

(1) arrange multiple displacement transducer at the detection end face of described pipe part, displacement transducer is vertically arranged on end face;

(2) shift value of detection is sent to microcomputer by described multiple displacement transducer;

(3) maximal value of the shift value received is deducted minimum value and obtains flatness tolerance value by described microcomputer.

11. 1 kinds utilize pick-up unit as claimed in claim 7 to carry out the detection method of roundness tolerance to pipe part, it is characterized in that: comprise the steps:

(1) 2 displacement transducers are respectively set at the two ends of orthogonal two diameters of described pipe part;

The shift value of detection is sent to microcomputer by (2) 4 displacement transducers;

(3) shift value received is calculated two diameter values by described microcomputer, major diameter value is deducted minor diameter value and obtains roundness tolerance value.

12. 1 kinds utilize pick-up unit as claimed in claim 8 to carry out the detection method of roundness tolerance to pipe part, it is characterized in that: comprise the steps:

(1) tube wall in the same cross section of described pipe part uniformly arranges 3 displacement transducers in 120 degree;

The shift value of detection is sent to microcomputer by (2) 3 displacement transducers;

(3) described microcomputer goes out concentricity tolerance value Δ according to following formulae discovery _t:

${\mathrm{\Δ}}_t=\sqrt{{\mathrm{\ΔX}}^2+{\mathrm{\ΔY}}^2}$

Δ R in formula ₁, Δ R ₂with Δ R ₃be respectively the displacement that 3 displacement transducers detect.