CN1022200C - Cam Shaft computer-aided measuring method and device - Google Patents
Cam Shaft computer-aided measuring method and device Download PDFInfo
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- CN1022200C CN1022200C CN 91108764 CN91108764A CN1022200C CN 1022200 C CN1022200 C CN 1022200C CN 91108764 CN91108764 CN 91108764 CN 91108764 A CN91108764 A CN 91108764A CN 1022200 C CN1022200 C CN 1022200C
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Abstract
The present invention relates to an auxiliary measuring method and a device for a cam shaft computer. The method of the present invention can measure any point on cam profile; lift data of each point can be orderly measured with equal phases, and phase difference delta a=sigma delta-i*the absolute value of (h-i-h-(i-h)) /2H-max; then phases delta a of measured data curves is amended to obtain square errors and errors with minimum lift. When the measuring device of the method is used, a control triggering circuit and a low resolution phase sensor with absolute zero positions are adopted in a data acquisition system of the measuring device; the present invention has the advantages of simple circuit, cost reduction, and accurate and reliable measurement result.
Description
The present invention relates to the measuring technique of contour curve, specifically, it relates to the Shaft computer-aided measuring method and the device of angle between a kind of lift range error of measuring the camshaft overhead cam and cam.
In cam design, generally be to be the lift starting point with the some points on the cam base circle, press the every corresponding phase value of polar coordinates, provide a standard lift range value.The cam contour surface that processes is a smooth curved surface, no any technological datum on the cam contour of lift starting point.In theory, in the camshaft measuring process, so point is arranged, can be so that be minimum with this quadratic sum as the lift range error of cam lift starting point gained, this point is called as the best measuring point that rises.In prior art, the basic skills of measuring camshaft is as follows: the mean radius that some spots calculates basic circle is got at the basic circle position at cam contour, with average base radius as zero lift, choose design and go up the standard lift range value of certain point of the lift variation rate sensitive part of stipulating, the rotating cam axle, the data that make lift range sensor record just equal this standard lift range value, obtain the phase value that camshaft turns over and the phase differential of this standard phase value then, play measuring point with phase value corresponding point on cam contour that difference is equal therewith as the best, measure the lift range value of each point, and go up the specified standard lift range value with design and compare, draw lift range error.By above-mentioned measuring method as can be seen, in prior art, the best definite order of accuarcy of measuring point that rises is the key of evaluation THE CAM PROFILE ERROR.In order to obtain the basic circle mean radius more exactly, need much more as far as possible to get a little; Because there is error in processing, actual phase value at certain sensitive spot of choosing on the cam contour might not be a specified standard phase value in the design, in order to obtain the best phase value that plays measuring point more exactly, requiring as far as possible, the several sensitive spots of multiselect average processing; In order to obtain the best phase value that plays measuring point more exactly, also require to adopt the high as far as possible phase detector of expensive resolution.Owing to rise in the determining of measuring point in the best and to exist random factor inevitably, thereby can have a strong impact on the reliability of evaluating THE CAM PROFILE ERROR, so the expert of relevant this respect has spent very big effort and has sought effective bearing calibration and (see the 2nd phase of " measurement technology " nineteen ninety, Liu Xingfu, " discriminating of cam lift graph of errors and correction ").The survey sensor of any measure of precision all can have certain error.Generally be to adopt the instrument of degree of precision that used sensor is examined and determine in prior art, determine a series of fixing error correction values in advance, the corresponding error correction values of handle directly is added to and carries out the precision correction on each measurement data in measuring process, and this precision correcting method is applicable to the measurement to unitary variant.And in the camshaft measuring process, because the characteristic of cam contour determines, phase place and lift have one to one relation, the lift range error that same phase place modified value causes on the diverse location of cam contour be different, difference is very big sometimes, can't determine in advance.Therefore, in camshaft is measured, generally also all try one's best and directly adopt the very high high precision phase detector of cost.Along with development of computer, adopt computing machine to carry out subsidiary both at home and abroad more and more.For example by the camshaft detector of describing in the camshaft computer aided measurement device of Shanghai Machinery College and Beijing Internal-Combustion Engine General Factory's joint research and development and the CN87208774U utility application, its measuring method and above-mentioned prior art are basic identical.Because the needs on the measuring method, the resolution of phase detector that requires these devices was up to 2 seconds, therefore remove and require to justify the many as far as possible grooves of primary sensing element grating dish of mounting for grating, need also to utilize that the secondary instrument circuit amplifies, shaping, phase shift, declare to, nearly a hundred times segmentation and reversible counting.Because phase detector is the active sensor in the measuring process, the secondary instrument circuit will influence the dynamic perfromance of measurement mechanism to the delay effect of signal Processing.Abroad, the camshaft measuring method that the UMC850 three coordinate measuring machine that Germany OPTON company produces adopts, attempt is according to the distribution of lift range error, utilize successive approximation method correction, make the quadratic sum of its error be tending towards minimum, but still requirement must be selected near the cam lift starting point playing a measuring point.Therefore its degree of closeness that plays measuring point and cam lift starting point also will directly influence the speed and the precision of whole measuring process.
The purpose of this invention is to provide a kind of cam Shaft computer-aided measuring method and device, use this method and apparatus, with any on the cam contour a bit as playing a measuring point, camshaft is only rotated a circle, the error sum of squares that can accurately measure a cam is minimum lift range error, and can accurately obtain the angle between the cam.
The objective of the invention is to realize by following method and apparatus.
A kind of cam Shaft computer-aided measuring method, it adopts the following step:
(1) will measure master routine, data acquisition program, precision revision program, curve fitting procedure, lift range sensor and phase detector error correction values and tested camshaft normal data deposits in the storer of system;
(2) system works, the log-on data capture program, with on the cam contour arbitrarily a bit as playing a measuring point, measure the lift data of each point in proper order with equal phase intervals, and write down the phase value of corresponding measured point, turn over till 360 ° up to tested cam;
(3) start the precision revision program, according to the lift range sensor error correction values each lift measurement data is revised earlier, according to error correction values and adjacent two lift measurement data of phase detector the rate of change of phase place is revised each lift measurement data once more then, the modified value computing formula of the lift range error that phase error is caused is △ h
i=δ α
i* | h
i-h
I-1|/θ, in the formula: modified value δ α
iBe i point phase error corrections value (degree), h
iFor the i point records actual lift data (mm), h
I-1For the i-1 point records actual lift data (mm), θ is the angle (degree) that phase detector that i~i-1 is ordered turns over;
(4) start curve fitting procedure, obtain the phase differential of measured data curve and normal data curve with method of weighted mean, then the measured data curve is carried out the phase place correction, draw its error sum of squares and be minimum cam lift error, the ultimate principle of its match is: cam contour is expanded into the planimetric rectangular coordinates curve, horizontal ordinate is the phasing degree, ordinate is a lift range value, at first the each point of the standard lift data of tested cam is depicted an approximately continuous standard lifting curve in rectangular coordinate system, with the actual lift outline data that records, depict an actual lift curve again with same method.In fit procedure, in the actual lift curve, check in earlier lift data h
i, and obtain α according to its position in measurement data
i(the 1st data α
oα after=0
iIncrease progressively with the phase sample interval θ that equates, so α
i=i * θ), then with this h
iCan in the standard lifting curve, calculate the theoretical standard phase beta of this point
i, α so
i-β
iBe exactly with h
iThe measurement starting point phase error △ α that this point calculates
i, all can calculate a phase differential △ α with the every bit on the lift equally, because same phase differential is in the diverse location of the lift difference that influences to lift, thereby should get its weighted mean value, its flexible strategy should be | H
i-H
I-1|/∑ | H
i-H
I-1|, ∑ | H
i-H
I-1|=2H
Max, in the formula: H
i, H
I-1Be respectively the standard lift range value that i, i-1 are ordered, H
MaxMaximum standard lift range value for cam contour.Actual measurement plays the phase differential △ α=∑ △ α of measuring point and theoretical starting point like this
i| H
i-H
I-1|/(2H
Max).To survey the phase place correction △ α of lifting curve then, and can calculate its error sum of squares and be minimum lift range error data, △ α is that theoretical starting point is the actual phase differential that plays measuring point;
(5) phase differential of survey cam and first cam measured data curve and normal data curve is compared, obtain the angle between the cam of surveying and first cam;
(6) start output device, draw the error figure of each cam and print lift range error and cam between the angle data.
In the measuring method of the present invention, the equal phase that measures each point lift data is advisable with 1 ° at interval.
Realize the computer aided measurement device of above-mentioned measuring method, its data acquisition system (DAS) is made up of lift range sensor, the phase detector with absolute zero position, gate circuit, frequency division/counting circuit, control triggering electric circuit, data buffer circuit, decoding scheme, the parallel input/output interface circuit PIO of computing machine and CPU (central processing unit) CPU.CPU is connected with PIO by data bus, PIO connects the control triggering electric circuit reset terminal, the zero pulse output terminal of phase detector connects the trigger end of control triggering electric circuit, the output terminal of control triggering electric circuit connects the control end of gate circuit, phase detector phase impulse output terminal connects the input end of gate circuit, gate output connects the input end of frequency division/counting circuit, the terminal count output of frequency division/counting circuit connects cpu data bus, PIO connects the input end of decoding scheme by address bus, the output terminal of decoding scheme connects the control end of data buffer circuit, the input end of data buffer circuit connects lift range sensor, the output terminal of data buffer circuit connects by data bus and connects PIO, CPU makes control triggering electric circuit be changed to the triggering state by PIO, the zero pulse of phase detector makes control triggering electric circuit trigger upset, open gate circuit, the phase pulse signal that phase detector sends is delivered to frequency division/counting circuit by gate circuit and is carried out after frequency division counter handles, be sent to PIO and CPU, CPU sends gating signal according to phase signal controlling and driving decoding scheme to data buffer circuit, then by the lift data in the data bus reading of data buffer circuit.After having surveyed 360 °, CPU sends reset signal by PIO to the control triggering electric circuit reset terminal, and the output terminal of control triggering electric circuit is overturn once more, closes gate circuit.
Between frequency division/counting circuit and PIO, can increase lengthened pulse trigger circuit, its trigger end connects the frequency division output terminal of frequency division/counting circuit, reset terminal connects the phase impulse output terminal of phase detector, its output terminal connects PIO, it is the same wide so just the phase impulse of exporting with phase detector to be arrived in the frequency division of frequency division/counting circuit output pulse widening, makes CPU time enough be arranged with inquiry mode work.
Measurement mechanism of the present invention technical scheme preferably can be that the resolution with phase detector of absolute zero position can be low to moderate 1 °.
Measurement mechanism of the present invention technical scheme preferably can be that the rotate a circle umber of pulse sent of phase detector with absolute zero position is 360 integral multiple.
Because measuring method of the present invention utilizes computing machine by method of weighted mean measured data curve and normal data curve to be carried out best-fit, thereby can measure by beginning more arbitrarily on cam contour, need not seek the best measuring point that rises, simplified testing procedure, shorten Measuring Time, and can draw the angle between the cam lift sum of errors cam that its error sum of squares is a minimum reliably.Error correction values and adjacent two lift measurement data according to phase detector are revised the lift measurement data to the rate of change of phase place, have overcome the lift measurement data error that the error owing to phase detector causes, make measurement result more reliable.
Owing to adopted the measurement mechanism of realizing measuring method of the present invention, greatly reduce harsh requirement to phase detector resolution, thereby significantly reduced the volume of phase detector, simplified circuit structure, improved the antijamming capability of device, improve the frequency response characteristic of device, and reduced the cost of measurement mechanism significantly.
Accompanying drawing 1 is the schematic diagram according to a camshaft computer aided measurement device of the present invention.
Accompanying drawing 3 is the measurement main program flow chart according to camshaft measuring method of the present invention.
Accompanying drawing 4 is the data acquisition program process flow diagram of above-mentioned measuring method.
Accompanying drawing 5 is the precision revision program process flow diagram of above-mentioned measuring method.
Accompanying drawing 6 is the curve fitting procedure process flow diagram of above-mentioned measuring method.
Describe optimum implementation of the present invention in detail below in conjunction with accompanying drawing.
In order to narrate conveniently, describe according to camshaft computer aided measurement device of the present invention earlier.Referring to accompanying drawing 1, in the data acquisition system (DAS) of this measurement mechanism, lift range sensor adopts long grating, phase detector adopts the photoelectric encoder with absolute zero position, this one week of scrambler is sent 1080 pulses, be per 20 ' one pulses, gate circuit T1 is made of Sheffer stroke gate, frequency division/counting circuit U2 adopts Z80-CTC timing/counting interface chip, control triggering electric circuit T3 and pulse widening trigger circuit T4 are made of JK flip-flop, data buffer circuit U4, U5, U6 is made of the ternary data buffer circuit of 8 buses of depositing with lock, what decoding scheme U3 used is the 3-8 decoding scheme, the parallel input/output interface circuit U1 of computing machine is Z80-PIO, and CPU (central processing unit) is Z80-CPU.The PA5 end of Z80-PIO is connected to the CLR end of trigger T3 by line 13, the absolute zero position pulse signal of photoelectric encoder is delivered to the CLK end of trigger T3 by line 8, the Q output terminal of trigger T3 is received the first input end of Sheffer stroke gate T1 by line 16, the phase pulse signal of photoelectric encoder is delivered to second input end of Sheffer stroke gate T1 by line 7, also delivers to the CP end of data buffer circuit U4.U5.U6 and the CLR end of pulse widening trigger circuit T4 respectively by line 7.The output terminal warp 10 of T1 is received the CLK/TRG0 end of U2, and U2 transmits data by data bus 1 to CPU, and the ZC/TO0 of U2 receives the CLK end of CLK/TRG1 end and T5 by line 12.The PA0 of U1~PA3 end is connected with decoding scheme U3 by address bus 2.The output terminal Y0.Y1.Y2 of U3 is connected with the CE control end of data buffer circuit U4.U5.U6 by line 4.5.6 respectively.Data buffer circuit U4.U5.U6 delivers to the lift signal that records PB0~PB7 end of U1 by data bus 3.
Introduce the course of work of data acquisition system (DAS) below in conjunction with accompanying drawing 2.When the PA5 of PIO end was low level, T3 was in reset mode, kept its Q end to be low level, and the T1 door is closed.CPU makes the PA5 end output high level of PIO, thereby make T3 become the state that to trigger, the CLK end of T3 is delivered in the upper edge of photoelectric encoder absolute zero position pulse, making the Q end of T3 is high level by the low level upset, data acquisition is opened and be maintained to the T1 door finish, when CPU makes the PA5 end output low level of PIO till.The phase impulse of photoelectric encoder output when the phase impulse lower edge, makes T4 be in the state that can trigger after T2 is anti-phase, and T4 is resetted; Phase impulse is delivered to U2 after the T1 door is anti-phase 0 passage carries out the frequency division processing, and the counting constant of 0 passage is predisposed to 3, just turns over 1 ° of interval every 3 phase impulse cams, and 0 passage of U2 is just exported a pulse.The CLK end of pulse widening trigger T4 is delivered in this divided pulse, and the Q end that so just makes T4 is that the PA4 that high level is delivered to PIO holds by the low level upset when the lower edge of phase pulse signal, and the upper edge that is maintained to phase impulse when T4 is resetted till.PIO control code translator U3 sends gating signal to data buffer circuit U4.U5.U6 in the meantime, by the lift data in the B mouth reading of data buffer circuit of PIO.Because the low level of phase impulse makes lift data latching that long grating records in data buffer circuit U4.U5.U6, so as long as CPU is when the Q of T4 end instructs for inquiring sampling between high period, data in the data buffer circuit that is read, be exactly the measured data of long at that moment grating in the phase impulse lower edge, so just guaranteed sampling precision, made system have the better dynamic characteristic.
Be described in detail the measuring method of present embodiment below in conjunction with accompanying drawing 3~accompanying drawing 6.
Before measuring, pack in the storer of system measuring master routine, data acquisition program, precision revision program, curve fitting procedure, long grating error modified value, photoelectric encoder error correction values.Tested camshaft be installed in according to measurement mechanism of the present invention two top between, corresponding with the photoelectric encoder absolute zero position measuring point that rises that a bit is arbitrarily in the measuring process on the cam contour.
Referring in the accompanying drawing 3 for measuring main program flow chart.After the startup master routine is started working, carry out frame 1 earlier, will long grating error modified value δ
i, photoelectric encoder error correction values δ α
iThe specified memory unit of packing into.Enter frame 2, the system request keyboard is imported the file name of tested cam normal data.Decision block 3 judges whether to be new file: if new file is then carried out frame 4 and frame 5, ask to import from keyboard the normal data of this cam, after the deposit, return and re-execute frame 2 and frame 3; If not new file, then carry out frame 6, the normal data in this document is called in the internal storage location of master routine appointment.After decision block 7 waits begin to measure keyboard instruction, treat that input begins to measure keyboard instruction, then carry out the data acquisition program shown in the frame 8, be the lift data that 1 ° of interval measures each point on the cam with the phase intervals that equates.Surveyed after the week, entered the precision revision program shown in the frame 9, the lift data that measure are just being studied.In the curve fitting procedure shown in the frame 10, obtain the phase differential of measured data curve and normal data curve with method of weighted mean, the measured data curve is carried out the phase place correction, and draw its error sum of squares and be minimum cam lift error.Enter frame 11, the phase differential of the measured data curve of survey cam and first cam and normal data curve compared, obtain the angle between the cam of surveying and first cam.At decision block 12, whether inquiry will measure next cam then; Wait input keyboard instruction: if measure next cam, then input " Y " on keyboard, program turns back to frame 2, if cam has all been surveyed, then input " N " on keyboard, enter frame 13, start output device, draw the error figure of each cam and print lift range error and cam between the angle data.
Referring to the data acquisition program process flow diagram in the accompanying drawing 4.After the inlet, carry out frame 8.1, data acquisition address pointer P1 is set.In 8.2 couples of parallel EingangsAusgangsSchnittstelle PIO of frame initialization: specify A mouth, the B mouth of PIO all to work in working method 3; PB0~the PB7 of B mouth all works in input mode, is used for lift data in the read data buffer; PA0~the PA3 of A mouth works in the way of output, be used for controlling decoding scheme the data impact damper is sent the decoding gating signal, PA4 works in input mode, be used for inquiring about whether the sampling instruction is arranged (become high level by low level and be the sampling instruction), PA5 works in the way of output, is used for the reset terminal of control triggering electric circuit.After the initialization, carry out frame 8.3, the PA5 output low level resets T3, closes the T1 door.8.4 pairs of timing of frame/counting circuit CTC initialization: specify 0,1,2 passages of CTC all to be operated in counting mode, 0 channel counts constant is changed to 3, makes 3 phase impulses of the every reception of 0 passage just send a pulse at ZC/TO 0 end, realizes 3 frequency divisions; 1 channel counts constant is changed to 180,2 channel counts constants and is changed to 2, is used for the phase impulse of 0 passage output is carried out 360 countings.Carry out frame 8.5 after the CTC initialization, the PA5 end output high level of PIO, make T3 be in the state that to trigger, the absolute zero position pulse for the treatment of photoelectric encoder makes the T3 upset, open T1 behind the door, 0 passage of CTC begins to receive the phase impulse that photoelectric encoder sends, 3 pulses of later every appearance, the ZC/TO0 end of CTC will be by T4 to impulse sampling instruction of the PA4 of PIO end output, and promptly PA4 end input signal becomes high level by low level.Whether the PA4 end of decision block 8.6 inquiry PIO becomes high level by low level: if do not have, then continue to wait for; If become high level, then carry out frame 8.7, the lift data of data buffer circuit are sampled, and will adopt data deposit the unit of the temporary address pointer P1 appointment of data acquisition in.Frame 8.8 will be kept in address pointer P1 and be added 1.Frame 8.9 reads in the phase data of 1, the 2 passages record of CTC, and deposits the unit of pointer P1 appointment in.Frame 8.10 will be kept in address pointer P1 and be added 1.Decision block 8.11 judges whether phase place turns over 360 °; If no, then repeat frame 8.6~8.11; If phase place has turned over 360 °, then return master routine by frame 8.12.
Referring to the precision revision program process flow diagram in the accompanying drawing 5.Behind the inlet, carry out frame 9.1, long grating modified value address pointer P1 is set.Carry out frame 9.2, photoelectric encoder modified value address pointer P2 is set.Carry out frame 9.3, acquired data storage device address pointer P3 is set.Revise earlier by the error of long grating and give the influence that records data tape.Carry out frame 9.4, get the lift data h that has gathered in the indicated unit of P3 pointer
iCarry out frame 9.5, according to h
iCalculate the value of long grating modified value address pointer P1, inquire corresponding to h according to the P1 value
iLong grating modified value δ
iCarry out frame 9.6, to h
iCarry out precision correction h
i=h
i+ δ
iAt frame 9.7, image data address pointer P3 adds 1, prepares for revising next sampled data.Judge whether to have revised whole 360 sampled datas at decision block 9.8: if do not have, then repeat frame 9.4~9.8, continue to revise next sampled data; After all having revised 360 sampled datas, enter frame 9.9, make i=0.Carry out frame 9.10, making, acquired data storage address pointer P3 resets.Not only the error of long grating is influential to the lift data that record, and the error of photoelectric encoder is also influential to it, also needs to revise.Carry out frame 9.11, the lift data h in the indicated unit of fetch pointer P3
iFrame 9.12 makes memory address pointer P3 add 1, points to next lift data.Frame 9.13 is got the lift data h in the P3 indicating member
I+1And pairing phase angle [alpha]
I+1, frame 9.14 is according to α
I+1Calculate the phase place modified value address pointer P2 of pairing this angular light photoelectric coder.Frame 9.15 is got the phase place modified value δ α in the P2 indicating member
I+1Calculate δ α at frame 9.16
I+1To the influence of lift and revise h
I+1=h
I+1+ (h
I+1-h
i) δ α
I+1Frame 9.17 makes i add 1.Decision block 9.18 judges whether to have revised 360 whole data: if do not have, then repeat frame 9.11~9.18, continue to revise next data; After all having revised 360 data, carry out frame 9.19, return master routine.
Referring to the curve fitting procedure process flow diagram in the accompanying drawing 6.Behind the inlet, carry out frame 10.1, lift normal data memory address pointer P1 is set.Frame 10.2 is provided with measurement data memory address pointer P2, and frame 10.3 makes i=0.Frame 10.4 is got the lift data h of P2 indication memory address
iAnd pairing angle [alpha]
iFrame 10.5 makes J=0.Frame 10.6 is got the standard lift data H of P1 indication
jFrame 10.7 adds 1 with standard lift data address pointer P1.Frame 10.8 is got the standard lift data H of P1 pointer indication
J+1, frame 10.9 makes J=J+1, prepares for getting next normal data.Decision block 10.10 is judged h
iWhether be positioned at H
jAnd H
J+1Between, if not then repeating frame 10.6~10.10, order is got an adjacent data again, until h
iBetween certain two adjacent normal data, frame 10.11 calculates measures lift data h
iPhase place α
iPhase differential △ α with the pairing notional phase of corresponding standard lift data
i=(J-1)+(H
J+1-h
i)/(H
J+1-H
j).Therefore the phase differential of different lift location obtains the phase differential △ α=∑ △ α of measured data curve and normal data curve to the difference that influences of lift with method of weighted mean
i(H
I+1-H
i)/2H
MaxCalculate its weights P=|H at frame 10.12
J+1-H
j|/2H
MaxFrame 10.13 accumulation calculating go out weighted mean phase differential △ α=△ α+△ α
iP.Frame 10.14 makes i=i+1, P2=P2+1 decision block 10.15 judge whether that match finishes whole cornerites: if do not have, then repeat frame 10.4~10.15; After all match finishes, enter frame 10.16, the measured data curve is carried out the phase place correction, draw its error sum of squares and be minimum cam lift error.Return master routine at frame 10.17.
Claims (6)
1, a kind of cam Shaft computer-aided measuring method is characterized in that adopting the following step:
(1) will measure master routine, data acquisition program, precision revision program, curve fitting procedure, lift range sensor and phase detector error correction values and tested camshaft normal data deposits in the storer of system;
(2) system works, the log-on data capture program, with on the cam contour arbitrarily a bit as playing a measuring point, measure the lift data of each point in proper order with equal phase intervals, and write down the phase value of corresponding measured point, turn over till 360 ° up to tested cam;
(3) start the precision revision program, according to the lift range sensor error correction values each lift measurement data is revised earlier, according to error correction values and adjacent two lift measurement data of phase detector the rate of change of phase place is revised each lift measurement data once more then;
(4) start curve fitting procedure, obtain the phase differential △ a=∑ △ α of measured data curve and normal data curve with method of weighted mean | H
i-H
I-1|/2H
Max, in the formula: △ α
iBe actual measurement phase place and the theoretical standard phase differential that i is ordered, H
i, H
I-1Be respectively the standard lift range value that i, i-1 are ordered, H
MaxMaximum standard lift range value for cam contour carries out the phase place correction to the measured data curve then, draws its error sum of squares and is minimum cam lift error;
(5) the measured data curve of survey cam and first cam and the phase differential of normal data curve are compared, obtain the angle between the cam of surveying and first cam;
(6) after all cam has all been surveyed on the tested camshaft, start output device, the sum of errors cam angle data of drawing each cam.
2, measuring method according to claim 1 is characterized in that said equal phase is advisable with 1 ° at interval.
3, a kind of computer aided measurement device that uses the described measuring method of claim 1, the data acquisition system (DAS) of this measurement mechanism comprises lift range sensor, phase detector, frequency division/counting circuit, data buffer circuit, decoding scheme, parallel input/output interface circuit PIO of computing machine and CPU (central processing unit) CPU, it is characterized in that it also comprises control triggering electric circuit, gate circuit, and phase detector adopts the phase detector with absolute zero position, CPU is connected with PIO by data bus, PIO connects the control triggering electric circuit reset terminal, the zero pulse output terminal of phase detector connects the trigger end of control triggering electric circuit, the output terminal of control triggering electric circuit connects the control end of gate circuit, phase detector phase impulse output terminal connects gate circuit and input end, gate output connects the input end of frequency division/counting circuit, the terminal count output of frequency division/counting circuit connects cpu data bus, frequency division output terminal connects PIO, PIO connects the input end of decoding scheme, the output terminal of decoding scheme connects the control end of data buffer circuit, the input end of data buffer circuit connects lift range sensor, the output terminal of data buffer circuit connects by data bus and connects PIO, CPU makes control triggering electric circuit be changed to the triggering state by PIO, the zero pulse of phase detector makes control triggering electric circuit trigger upset, open gate circuit, the phase pulse signal that phase detector sends is delivered to frequency division/counting circuit by gate circuit and is carried out after frequency division counter handles, be sent to PIO and CPU, CPU sends gating signal by PIO controlling and driving decoding scheme to data buffer circuit according to phase signal, then by the lift data in the data bus reading of data buffer circuit, after having surveyed after 360 °, CPU sends reset signal by PIO to the control triggering electric circuit reset terminal, the output terminal of control triggering electric circuit is overturn once more, close gate circuit.
4, computer aided measurement according to claim 3 is characterized in that described resolution with phase detector of absolute zero position can be low to moderate 1 °.
5, computer aided measurement device according to claim 3 is characterized in that the rotate a circle umber of pulse sent of described phase detector with absolute zero is 360 integral multiple.
6, a kind of computer aided measurement device that uses the described measuring method of claim 1, the data acquisition system (DAS) of this measurement mechanism comprises lift range sensor, phase detector, frequency division/counting circuit, data buffer circuit, decoding scheme, parallel input/output interface circuit PIO of computing machine and CPU (central processing unit) CPU, it is characterized in that it also comprises control triggering electric circuit, gate circuit, the lengthened pulse trigger circuit, and phase detector adopts the phase detector with absolute zero position, CPU is connected with PIO by data bus, PIO connects the control triggering electric circuit reset terminal, the phase impulse output terminal of the device of the zero pulse output terminal connection control triggering electric circuit of phase detector connects the input end of gate circuit, the output terminal of gate circuit connects the input end of frequency division/counting circuit, the terminal count output of frequency division/counting circuit connects cpu data bus, frequency division output terminal connects the trigger end of circuit for stretching pulse, the reset terminal of lengthened pulse trigger circuit is connected with the phase impulse output terminal of phase detector, the output terminal of lengthened pulse trigger circuit is connected with PIO, PIO connects the input end of decoding scheme, the output terminal of decoding scheme connects the control end of data buffer circuit, the input end of data buffer circuit connects lift range sensor, the output terminal of data buffer circuit connects by data bus and connects PIO, CPU makes control triggering electric circuit be changed to the triggering state by PIO, the zero pulse of phase detector makes control triggering electric circuit trigger upset, open gate circuit, the phase pulse signal that phase detector sends is delivered to frequency division/counting circuit by gate circuit and is carried out after frequency division counter handles, counting output is sent to CPU, frequency division output is sent to PIO through the lengthened pulse trigger circuit, CPU sends gating signal by PIO controlling and driving decoding scheme to data buffer circuit according to phase signal, then by the lift data in the data bus reading of data buffer circuit, when having surveyed after 360 °, CPU sends reset signal by PIO to the control triggering electric circuit reset terminal, the output terminal of control triggering electric circuit is overturn once more, close gate circuit.
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Application Number | Priority Date | Filing Date | Title |
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CN 91108764 CN1022200C (en) | 1991-09-05 | 1991-09-05 | Cam Shaft computer-aided measuring method and device |
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CN 91108764 CN1022200C (en) | 1991-09-05 | 1991-09-05 | Cam Shaft computer-aided measuring method and device |
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CN1061475A CN1061475A (en) | 1992-05-27 |
CN1022200C true CN1022200C (en) | 1993-09-22 |
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CN 91108764 Expired - Fee Related CN1022200C (en) | 1991-09-05 | 1991-09-05 | Cam Shaft computer-aided measuring method and device |
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Families Citing this family (5)
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CN104501850B (en) * | 2014-11-19 | 2017-02-01 | 第一拖拉机股份有限公司 | Calibration camshaft measuring instrument etalon and using method thereof |
CN105136023B (en) * | 2015-04-28 | 2017-11-28 | 上海交通大学 | Half assembling engine crankshaft phase recognition methods and device |
CN105277159A (en) * | 2015-10-27 | 2016-01-27 | 第一拖拉机股份有限公司 | Method used for modifying camshaft lift detection start point and acquiring detection result |
CN109556532B (en) * | 2018-11-22 | 2019-11-15 | 中国科学院西安光学精密机械研究所 | Automatic detection system and method for cam curve |
CN112796846B (en) * | 2021-02-05 | 2022-04-08 | 联合汽车电子有限公司 | Method, device and equipment for identifying deviation of engine camshaft and storage medium |
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1991
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