The measuring method of the static steering resisting moment of a kind of shovel loader
Technical field
The present invention relates to a kind of measuring method of moment, specifically the measuring method of static steering resisting moment during a kind of shovel loader pivot stud, belongs to loading machine steering torgue measurement technical field.
Background technology
Shovel loader normal operation, transport and traveling time need frequently to turn to, the difficulty or ease turned to whether direct relation performance and the work efficiency of complete machine, therefore to turn to be one of very important performance of complete machine.Complete machine is when fully loaded or overload transportation, due to the restriction that work-yard is narrow and small, frequent needs turn to less radius of turn, when redirecting to extreme position, there will be the situation turning to difficulty or turning rate comparatively to require great effort, once after complete machine turns over extreme position, turn to and just become relatively easy.Think: when the steering moment only having steering cylinder to provide is greater than the steering resisting moment on ground, complete machine just can realize turning to; Large is more, then it is easier to turn to; Otherwise, then more difficult.Therefore, when designing new product, need to know that the steering resisting moment of same tonnage shovel loader has much, and the approximate relation between the parameter such as the friction factor on steering drag and ground, load, angle, namely the steering resisting moment when, under what state is maximum, thus changes design parameter targetedly and realize good economy.But the steering drag of shovel loader and the moment of resistance are difficult to hold, and the theoretical formula mentioned in various document all cannot estimate the occurrence of steering resisting moment relatively accurately.
Learnt by practical experience, the size of steering resisting moment is relevant with steering drag and steering cylinder, and steering drag is relevant with steering pressure again.And steering cylinder and choosing of steering pressure thereof are generally all decided according to existing experience at present, analogy method is namely adopted to determine.But the steering moment of the steering cylinder empirically selected often surplus capacity is larger, and cost is higher, and economy is bad, but the size that can not reduce oil cylinder easily meets, and surplus is smaller again when steering lock position.Therefore, the shortage of steering resisting moment correlation parameter, the economy making designer have to sacrifice complete machine meets.
The steering resisting moment estimating different tonnage shovel loader how can be relatively accurate, and requirement that steering resisting moment must meet and design margin both economical accordingly (safety coefficient) are proposed, then become urgent problem.So, whether can be met the demands by the steering moment of the existing shovel loader of investigation, if too more than needed, then can reduce system pressure or change to less steering cylinder to meet, thus reducing costs, improving product competitiveness; If steering moment surplus is too small, then need to improve system pressure or by steering cylinder overstriking etc. to increase steering moment, thus reduce the failure rate of steering, improve the functional reliability of complete machine, and then provide theoretical and data reference for the steering optimization of follow-up new product designs and old product.Therefore, the curve map of often kind of type steering resisting moment seems extremely important, and the surplus capacity of steering moment is one of direct factor determining complete machine economy and reliability.
Steering resisting moment is divided into two kinds: a kind of is static steering resisting moment, and another kind is the dynamic steering moment of resistance; The dynamic steering moment of resistance refers to (comprise pivot stud and turn in travelling) in complete machine normal direction of rotation process; And static steering resisting moment refers to that complete machine turns to instantaneous steering resisting moment by static, namely steering cylinder from without response to have response and flexible time corresponding steering resisting moment (only occurring during pivot stud).
Be greater than the theory of force of sliding friction according to maximum static friction force, tyre revolution to model be the lateral slip of tire and the resultant motion of lateral rotation, but slide while have rolling again.Accordingly, think that maximum static steering resisting moment is greater than the dynamic steering moment of resistance, therefore only need record maximum static steering resisting moment, and for the static steering resisting moment of shovel loader, prior art does not have effective measuring method.
Summary of the invention
For the technical matters of above-mentioned existence, the invention provides the measuring method of the static steering resisting moment of a kind of shovel loader, the static steering resisting moment of complete machine optional position can be obtained.
To achieve these goals, first theoretical analysis is carried out to the acquisition of the static steering resisting moment of shovel loader and correlative factor:
When complete machine original place slowly turns to, what can be similar to thinks the steering moment that steering resisting moment equals steering and provides, and complete machine turns to slower, and steering moment is more close to the actual value of steering resisting moment.Certainly, the pilot pressure that steering provides must promote the spool of steering main valve thus make steering cylinder have flexible response, and just the response action of oil cylinder is more slow better.And when by static, original place slowly turns to complete machine, what complete machine overcame is static steering resisting moment.
Accordingly, the measurement of steering moment when complete machine is slowly turned to by static just can be converted into for the measurement of the static steering resisting moment of shovel loader.And the condition that complete machine original place slowly turns to has following 2 points: 1, engine idling operation, 2. the rotating speed of bearing circle is more slow better, but will meet oil cylinder has flexible response.
Moment of resistance during owing to turning to than unloaded (weight on front axle accounting about 50%) when complete machine fully loaded (weight on front axle accounting about 75%) turns to is large, therefore can think that steering resisting moment and weight on front axle exist certain positive correlation, namely weight on front axle is larger, and steering resisting moment is larger.And the weight on front axle of shovel loader complete machine is fully loaded and swing arm is flat stretch time maximum, therefore another requirements of measuring method of the present invention is: complete machine is fully loaded with, and swing arm is in put down and stretches position.And when complete machine turns to, the load of propons can become large, therefore the steering resisting moment of propons also can become large, therefore can think that steering resisting moment and steering angle also exist certain positive correlation.
Comprehensive visible, the condition that measuring method of the present invention requires has: 1. neutral hung by complete machine, pivot stud; 2. complete machine is fully loaded with, and swing arm is in and flat stretches position; 3. engine idling operation; 4. bearing circle rotating speed (each type) with actual oil cylinder have the minimum bearing circle rotating speed of flexible response be as the criterion (close to minimum also can).
In order to verify above-mentioned deduction further, theoretical analysis can be carried out to the steering procedure Modling model of complete machine.
As shown in Figure 1, ABCDO form shovel loader turn to hinge model, O is the hinged central point of front/rear frame, and A, B, C, D are respectively the right hinge of Rear frame, the right hinge of front frame, the left hinge of front frame, the left hinge of Rear frame.And A point and D point, B point and C point are symmetrical relative to the longitudinal symmetrical plane in hinged center.Due to complete machine turn left to turn right to having symmetry, in order to study conveniently, suppose complete machine turn left to:
Current vehicle frame turned left any angle α time, the right hinge B of front frame forwards B ' to, the left hinge C of front frame forwards C ' to, AB ' is right oil cylinder hinge centre distance, DC ' is respectively OF, OE, then OB=OB '=OC=OC '=R for left oil cylinder hinge centre distance, the arm of force of left and right oil cylinder to hinged center O, AO=OD=L, initial angle β=∠ AOB=∠ DOC.
Have this: current vehicle frame turns left over-angle when being α, and the instantaneous steering moment M provided of complete machine steering is:
M=F
right* OE+F
left* OF=P*S
right* OE+P*S
left* OF is 1.,
Wherein, F
rightand F
leftrepresent right turn oil cylinder respectively, thrust that left steering oil cylinder produces complete machine; P is the instantaneous pressure of complete machine steering, P≤P
mAX(rated pressure), during overload, P=P
mAX, steering hydraulic system surplus valve is opened, and system starts overflow; During normal work, P < P
mAX; S
rightand S
leftbe respectively the useful area of right oil cylinder and left oil cylinder.
In △ AOB ', AB '
2=R
2+ L
2-2RLcos (β+α) 2.,
And the area of △ AOB ':
③,
2. and 3. can be released by formula:
④;
In like manner: in △ DOC ', have DC '
2=R
2+ L
2-2RLcos (β-α) 5.,
The area of △ DOC ':
⑥,
5. and 6. can be released by formula:
⑦。
Complete machine turn left to time, right turn oil cylinder extend, pressure oil is entered in the large chamber of right turn oil cylinder, loculus oil return (pressure is 0),
and left oil cylinder shortens, left oil cylinder loculus (connecting with the large chamber of right oil cylinder) enters pressure oil, large chamber (connecting with right oil cylinder loculus) oil return,
wherein, D is steering cylinder piston cylinder internal diameter, and d is diameter of piston rod.
By S
right, S
left, 1. 7. 4. formula substitute into the formula of steering moment M with formula, can draw:
That is:
⑧。
When not considering the interference of complete machine parts, for formula 7., as α=β,
namely F point overlaps with O point, and as shown in Figure 2, namely the left steering oil cylinder arm of force is 0, and the moment that left steering oil cylinder produces is 0; Now, left steering oil cylinder just reaches dead-centre position, does not contribute steering moment, only has right turn oil cylinder to have contribution, and namely the original task that turns to born by two steering cylinders has been come by an oil cylinder now, is equivalent to steering unbalance loading.For the steering hydraulic system of existing shovel loader, unbalance loading will inevitably cause pressure sharply to increase, until complete machine steering overflow (overload), namely steering cannot normally work.Therefore, the necessary condition that 7. formula is set up is: α < β.Therefore, the necessary condition that 8. formula is set up is: α < β.
Consider the interference of complete machine parts and the real data of existing product, α, the β value statistical form of each product are as follows:
Model |
3 tons |
4 tons |
5 tons |
6 tons |
7 tons |
8 tons |
9 tons |
10 tons |
12 tons |
α° |
38 |
35 |
38 |
38 |
40 |
40 |
40 |
40 |
40 |
β° |
76.5 |
72.9 |
75 |
77.8 |
80.4 |
80.4 |
80.4 |
80.7 |
92.2 |
Drawn by upper table: 35 °≤α≤40 °, 72.9 °≤β≤92.2 °, meet the condition of α < β, therefore 7. formula is set up, thus 8. release formula is set up.
In like manner, when complete machine by straight steering angle is α to the right time, because of symmetrical, therefore instantaneous steering moment M is with formula 8..
8. formula has versatility (as long as be consistent for other engineering machinery model of hydro-steering, above-mentioned analysis theories then has generalization) for the instantaneous steering moment calculating of existing product.
8. analyzed by formula: when steering procedure slowly time, utilize formula 8. can calculate static steering resisting moment.And formula 8. in R, L, β, D, d be known, P and α is unknown, and when P is the value of actual measurement, M is instantaneous steering resisting moment during steering angle α, and namely 8. formula can be used as the theoretical foundation of the static steering resisting moment measuring method of the present invention.
Based on above-mentioned theoretical analysis, the measuring method of the static steering resisting moment of a kind of shovel loader that the present invention adopts is:
First, the place selecting a slice floor synthetic friction factor consistent is as measurement place; Then, shovel loader is fully loaded with, and moved arm lifting stretch position to flat; Ensure that complete machine engine is in idle running, carries out pivot stud by complete machine by static simultaneously, measure steering pressure P and corresponding steering angle α, the instantaneous steering resisting moment formula provided of complete machine steering finally measured value is provided:
In formula, R is the distance at front frame hinge and hinged center, and L is the distance at Rear frame hinge and hinged center, β be front and back hinge and hinged in the initial angle that is formed centrally, D is steering cylinder piston cylinder internal diameter, and d is diameter of piston rod.The static steering resisting moment of shovel loader is converted into the measurement to the instantaneous steering moment of complete machine, and then the static steering resisting moment of complete machine optional position can be calculated.
Secondly, driver can promote with steering cylinder the minimum bearing circle rotating speed that vehicle frame carries out turning to and turn to, and when complete machine redirect to limit on the right-right-hand limit from limit on the left, bearing circle turns over based on the half of number of total coils, on this basis by its n equal portions, only measure n group data and extreme position data; Be that complete machine turns to by heading straight for the beginning during first group of DATA REASONING; When (i+1) organizes DATA REASONING, complete machine reference position is bearing circle from after complete machine turns over i × number of total coils/2n to straight state; When measuring for each cycle, driver all at the uniform velocity turns to minimum bearing circle rotating speed, and be no more than 1/4 circle of bearing circle each measuring period, wherein, n is positive integer, i=0,1,2,3 ... n-1.
The steering pressure P of described measurement is the instantaneous system force value that measurement complete machine slowly turns to by static.
Compared with prior art, the present invention is based on the theory of steering procedure model, corresponding measuring method is proposed, analysis principle is fairly simple, easy understand, avoid the complicated differential equation theoretical, to the accumulation degree of the technical know-how of researcher and user and difficulty less demanding, namely easy-to-understand.The independent variable that measuring method of the present invention is measured is less, only two, and each parameter is easy to measure, and can be obtained the static steering resisting moment of complete machine optional position by the measurement of two parameters.Therefore the surveying work of measuring method of the present invention implements relatively simple, avoids measure compared with multivariate the inconvenience brought simultaneously.The number of times that each independent variable is measured is less, avoids the higher labour intensity that lot of experiments number of times brings.Measuring method is simple, practical, easily realizes in the engineering survey of routine.The human cost that whole measuring method implements is less, and also less to the machine loss of shovel loader, whole measuring period is short, has larger cost advantage.Theoretical analysis result of the present invention can carry out design specifications to steering moment, forms module, easily as company standard, for the design of follow-up new product and improving and optimizating of old product provide data supporting and reference.Measurement mechanism does not need special test platform and device, only needs corresponding surveying instrument, and the scale of whole test is less, and it is high to implement efficiency, and cost advantage is obvious, and enterprise is acceptant and adopt.Theoretical generalization is good, and for other engineering machinery that all-hydraulic pair of oil cylinder turns to, above-mentioned analysis theories and measuring method then have promotional value.For static steering resisting moment, measuring method of the present invention requires that complete machine is fully loaded with, and moved arm lifting stretches position to flat, the measurement of the dynamic steering moment of resistance often swing arm at receipts bucket position or transporting position, therefore, measuring method thinking of the present invention is unique, and the data measured have more reference value (because swing arm to put down the weight on front axle stretched larger than transporting position, therefore the static steering resisting moment of complete machine is larger) than transporting position, this is also a spotlight of measuring method of the present invention.Another unique distinction of the present invention is that steering angle is prior to pressure survey, therefore, before measuring pressure, angle is known, and the pressure of correspondence be shovel loader by the static instantaneous pressure having response action to oil cylinder, and complete machine is the value of first pre-test by the steering angle of the static moment to action.Dynamic system pressure during normal direction of rotation does not belong to the measurement range of the inventive method.Another unique distinction of the present invention is to require pivot stud, engine idle, and driver slowly turns to, known according to theoretical analysis process of the present invention, like this could closer to the actual value of static steering resisting moment.The present invention is with the actual rotating cycle of bearing circle for implementing the foundation of measuring process, and driver is very easy to hold, and more convenient driver realizes handling complete machine, and this is also a spotlight of the present invention.Measuring method security of the present invention is high, and environmental protection, environmentally safe.
Accompanying drawing explanation
Fig. 1 is loading machine steering process model reduced graph of the present invention;
Fig. 2 is the model simplification figure in Fig. 1 as steering angle α=β;
Fig. 3 is the thinking derivation graph of measuring method of the present invention;
Fig. 4 is the concrete implementing procedure figure of measuring method of the present invention;
Fig. 5 is the stereographic map of seven tons of pouring weights;
Fig. 6 is the front view of seven tons of pouring weights;
Fig. 7 is the schematic diagram before driver complete machine spading pouring weight;
Fig. 8 is the schematic diagram that driver complete machine spading pouring weight rear bucket is set level;
Fig. 9 is the schematic diagram after driver complete machine spading pouring weight receives bucket;
Figure 10 is that driver complete machine spading pouring weight lifting swing arm is to the flat schematic diagram stretching position;
Figure 11 is the vertical view of Figure 10;
Figure 12 for driver by Figure 11 (complete machine is in straight state) turn left to schematic diagram;
Figure 13 is that bearing circle is turned left to the schematic diagram of 1/4 circle by initial position.
In figure: α, steering angle, the angle-data of Y, actual measurement, α=180 °-Y.
Embodiment
Specific embodiment: be example (adopt guide's hydrostatic control and Steering system with flow amplification) below in conjunction with accompanying drawing and Xu work 7 tons of shovel loaders, the invention will be further described.
7 tons of loading machine steering angles are 40 °, will measure the curve map that more data could draw static steering resisting moment in theory.In order to reduce test number (TN), measuring method of the present invention is only measured 10 (n=10) and is organized data and one group of extreme angles data, and the curve then can drawn according to test findings for remainder data judges.
Complete machine engine idling operation, the slow steering wheel rotation pivot stud of driver, complete machine forwards limit on the left bearing circle to by limit on the right-right-hand limit and about turns 10 circles (number of total coils), the mean speed of driver is 0.5 circle/second, from complete machine to straight (referring to accompanying drawing 11) to steering lock angle, bearing circle about turns 5 circles.(can be determined by the numerical value specifically measured from complete machine until the number of turns of steering lock angle and bearing circle mean speed for other complete machine)
In order to ensure the confidence level of data, measuring method of the present invention measures the pressure of 10 angles and an extreme angles and correspondence, (each angle needs survey twice, gets the mean value of two secondary data)
The measurement of 10 groups of data: the number of turns (5 circle) turned over bearing circle is benchmark.
First group: complete machine to angle time straight and starting turn left to pressure;
Second group: bearing circle by the angle of (0.5 circle) after directly turning over half-turn and turn left to pressure;
3rd group: bearing circle by the angle of (1 circle) after directly turning over 1 circle and turn left to pressure;
4th group: bearing circle by the angle of (1.5 circle) after directly turning over 1.5 circles and turn left to pressure;
……
9th group: bearing circle by the angle of (4 circle) after directly turning over 4 circles and turn left to pressure;
Tenth group: bearing circle by the angle of (4.5 circle) after directly turning over 4.5 circles and turn left to pressure;
Extreme position: in the angle of limit on the left position, starts the pressure that (to the right) round about turns to.
Turn to the cycle to be 1/4 circle, namely bearing circle turns over about 90 ° at every turn.
Equipment connection: as shown in Fig. 7 to Figure 11, at the pressure chamber place of left steering oil cylinder (or right turn oil cylinder), pressure measuring tie-in is installed, driver complete machine spading 7 tons of pouring weights (see accompanying drawing 7 and Fig. 8), then receiving bucket to scraper bowl limited block leans against on swing arm, ensure that receiving bucket puts (see accompanying drawing 9) in place, and moved arm lifting is stretched position (see accompanying drawing 10) to flat, adjustment direction dish, complete machine is in close to straight state (see accompanying drawing 11), unclamp gas pedal, ensure that complete machine stops at measured zone, and leave engine idling.Hand-held meter PPC is connected to the pressure measuring tie-in of steering cylinder pressure measurement interface by the pressure transducer supporting with measuring instrument, ensure the safe length (3 meters ~ 5 meters) of connecting line in steering procedure, the other end of pressure transducer is connected to the pressure interface of PPC, starts to prepare to measure:
First group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 0.5 circle (180 °) that then turned left by bearing circle stops afterwards, prepares the measurement of next group data;
Second group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 1 circle (360 °) that then turned left by bearing circle stops afterwards, prepares the measurement of next group data;
3rd group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 1.5 circles (540 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
4th group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 2 circles (720 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
5th group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 2.5 circles (900 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
6th group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 3 circles (1080 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
7th group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 3.5 circles (1260 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
8th group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 4 circles (1440 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
9th group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
Then driver turns right bearing circle, and make complete machine be in close to straight state, about 4.5 circles (1620 °) that then turned left by bearing circle stop afterwards, prepare the measurement of next group data;
Tenth group of DATA REASONING: first measure the angle formed between front/rear frame beam slab with inclinometer, measures twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is left to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
The measurement implementing procedure figure of above-mentioned ten groups of data refers to Fig. 4.
Because extreme position is likely the extreme point of steering resisting moment, the extreme position angle of every platform complete machine is known, but has the error of processing accumulation.For this reason, we must the angle of measuring limit position and system pressure.
By driver, complete machine is diverted to limit on the left position left, owing to being at extreme position for the last time, therefore cannot continue again to turn left to, but can turn right to.
First measure the angle formed between front/rear frame beam slab with inclinometer, measure twice, and recording angular value.After measurement of angle is complete, open hand-held meter PPC, within about 5 seconds in advance, press RECORD key → RECORD key → OK key, start to show force value, then driver is to the right to stop turning to close to after rotating speed uniform rotation bearing circle about 1/4 circle of 0.5 circle/second, the slightly delayed OK key pressing PPC for about 5 seconds again of registrar, then the pressure time curve pressing that SAVE key preserves measurement, terminate the measurement of this pressure.
After measuring, pilot control handle, is stretched position by swing arm dropped to transporting position by flat, then flame-out engine, complete machine is static, pulls down PPC measuring instrument and pressure transducer, then pouring weight is put back to original position by driver complete machine, thus completes whole measuring period.
PPC is connected to computer, reads pressure information by software.Pressure, angle value etc. are inserted table one:
Table one
Measurement data is substituted into 8. formula, calculate corresponding M, and draw the roughly curve of pressure, angle, moment.In order to analyze variation tendency, can be follow-up new product development and do data reference.