CN101226110A - Device and method for detecting descending braking distance of bridge crane hoisting mechanism - Google Patents

Abstract

The invention relates to a decreasing brake distance detecting device of hoist mechanism of bridge crane and a relative method. The device comprises a brake power-off inductor for sensing and detecting a trigger signal generated at the time that the brake turns off power supply, a digit sensor contacted with a steel wire reel to generate pulse signal, a metering device for receiving, metering and displaying a sensor pulse signal from the trigger signal, an error corrector for correcting the measurement error caused by rope groove width, rope groove depth and steel wire diameter. The invention can reasonably select test portion, utilize sensor technique and accurately measure the brake distance when the hoist mechanism lifts heavy object down, to provide a quantitative test device for integral property of crane, type test and safe property of crane, thereby providing technical reference for the brake property and adjustment evaluations of brake.

Description

Descending braking distance of bridge crane hoisting mechanism pick-up unit and method

Technical field

The invention belongs to distance detecting instrument technical field, particularly relate to a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit and method.

Background technology

Detent is the vitals that guarantees hoisting machinery safety operate as normal.In lifting job, detent is used to prevent that the article that suspend in midair from falling, and prevents the slippage of crane under wind action; Or operating mechanism is underspeeded, until finally out of service.The braking distance of detent has extremely tight and important getting in touch with safety in production, and it is the very important very important link that ensures safety in production.The overall performance test project of crane and type approval test project all require us can be correctly scientifically the braking distance of detent to be detected.GB/T14405-1993 " general-purpose overhead crane "; GB/T14406-1993 " gantry crane for general use "; JB/T1306-1994 " electric single beam crane "; And the braking distance of clearly illustrating crane hoisting mechanism in the JB/T2603-1994 standards such as " electric single-beam underhung cranes " is the examination project as specification product, and provided corresponding qualified index request.For a long time, owing to the reason on the measuring technology, cause these data can't accomplish correct test, to such an extent as to the unable correct adjustment of finishing detent installation back braking ability of manufacturing, installation, maintenance, maintenance and applying unit, make the degree of tightness adjusting of detent band-type brake be difficult to weigh, cause this test item of braking distance to be in the vacant state of no special testing instrument always with braking distance.

Summary of the invention

Technical matters to be solved by this invention provides a kind ofly can not dismantle any global facility at overhead travelling crane, under the normal prerequisite of using, correctly detect crane hoisting mechanism rapidly when low speed descends operation, under the nominal load effect, detent displacement--the pick-up unit of descending braking distance that lifting mechanism slides downwards owing to the potential action of lift heavy thing in braking procedure.

The technical solution adopted for the present invention to solve the technical problems is: a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit is provided, comprises:

Detent outage inductor: induction detects detent control power cut-off formed trigger pip of moment;

Digital transducer: the pulse signal that contacts and send with cable drum;

Measuring apparatus: acceptance is also measured from the sensor pulse signal after the trigger pip and is shown;

The error device of correcting errors in printing: get rid of the measuring error of bringing by grooving width, the grooving degree of depth and wirerope diameter.

Described detent outage inductor is composed in series by detent power supply, electric energy inductor, signal processor, level trigger.

Described digital transducer by the sampling roller, digital sensor, the long transmitter of two-phase arteries and veins, signal gain device, compose in series.

Inner being equipped with of described device can guarantee the normal accumulator that uses.

Described measuring apparatus comprises length measuring and range display.

The housing face-plate of described device comprises:

(a) display window---the high-speed counter by finished product constitutes counting; Be detected the coasting distance of reel or the umber of pulse of correspondence after being used for showing the detent outage;

(b) power switch locking press button---the power supply when being used for controlling the work of this detector, pressing self-locking is energized;

(c) power light---power light is bright when power switch is pressed power supply and is switched on;

(d) power supply capacity button---when pressing primary power source capacity button, the power supply capacity pilot lamp can show the capacity situation of detector internal cell storage;

(e) power supply capacity pilot lamp---show the situation of current detection instrument internal cell capacity storage, form by four lamps;

One of high order end is red, represents and must charge when bright separately; Three of all the other right-hand members are green; Four complete represents the power supply abundance when bright, and the power supplys that from left to right light three, two expression storages are according to this weakening;

(f) whether voltage triggered locking press button---it is normal to check triggering control to press this button when the selector switch on the rear panel places voltage location;

(g) voltage triggered pilot lamp---the voltage triggered pilot lamp is bright when the selector switch on the rear panel places voltage location;

The voltage triggered pilot lamp goes out when the voltage triggered locking press button is pressed, and it is normal that expression triggers control; The voltage triggered pilot lamp also goes out when detent is switched on;

(h) whether current trigger locking press button---it is normal to check triggering control to press the current trigger locking press button when the selector switch on the rear panel places Current Position;

(i) current trigger pilot lamp---the current trigger pilot lamp is bright when the selector switch on the rear panel places Current Position;

The current trigger pilot lamp goes out when the current trigger locking press button is pressed, and it is normal that expression triggers control; The current trigger pilot lamp also goes out when detent is switched on;

(j) current detecting pilot lamp---when the selector switch on the rear panel places Current Position, and insert on the current detecting socket of plate in the back current trigger with current inductor after, the current detecting pilot lamp is bright, the expression inductor is switched on;

(k) reel signal 1 lamp---expression is sent into the flicker expression from the first via detection signal of reel sensor;

(l) reel signal 2 lamps---expression is sent into the flicker expression from the second road detection signal of reel sensor;

Signal 1 and signal 2 differ 90 degree on circuit;

(m) tracer signal 1 lamp---expression has been sent into input end of counter from the pulse of reel signal 1;

(n) tracer signal 2 lamps---expression has been sent into No. two input ends of counter from the pulse of reel signal 2; Tracer signal 1 lamp and tracer signal 2 lamps extinguish simultaneously when pressing voltage triggered or current trigger locking press button, represent that two paths are working properly;

(o) counting commutation locking press button---because counter has positive and negative Presentation Function, supposition just drops in the ordinary course of things, rises to negatively, switches to the supposition situation with this button at an easy rate in test site so;

(p) counting locking locking press button---be to keep accurately can the count value maintenance being locked of data after the downslide braking distance has detected, in order to avoid change with this locking press button;

(q) reset button---when reel when descending one grade of stable operation, must the value on the counter be removed with reset button, return braking distance after zero to guarantee to measure exactly detent.

A kind of descending braking distance of bridge crane hoisting mechanism detection method comprises the following steps:

(1) records the grooving width and the degree of depth on wirerope diameter, the lifting mechanism reel with vernier caliper, record specified lifting velocity, with visual observation lifting hook pulley group multiplying power number, with these data error originated from inputs device of correcting errors in printing with the cooperation or the knotmeter of stopwatch and ruler;

(2) the complete machine screen will show the value of " specified umber of pulse ", " downslide coefficient " and " specified descending braking distance number ", " downslide coefficient " value wherein be inserted in the preset proportion PS.AX item scaling position of selected good dp item displayed value;

(3), select the connecting line of voltage or current trigger according to the kind of detent working power;

(4) open the upper semi-circle of current transducer, entangle detent service cable bonnet and tightly screw on; The sensor that has disk is fixed on the gauge stand support bar, makes disk abut against the smooth periphery of rope drum place, the magnetic switch of screwing on fixes gauge stand;

(5) follow reel when rotating together when the disk on the sensor, press the reset button on the front panel, the display zero clearing;

When handle was got back to zero-bit from keeping out, display will demonstrate the distance that the reel rotation is moved in the braking procedure, i.e. the descending braking distance value of lifting mechanism hook.

Described step (2) adopts the umber of pulse of descending braking distance correspondence, and its preset proportion PS.AX item is set to 1, and the dp item is made as integer.

Described step (3) if in voltage, then select three core connecting lines for use, the clip on the one end is clamped two power connection end in the detent terminal box, other end socket inserts in three corresponding on the detector rear panel core jacks; If big electric current is then selected the four-core connecting line for use, an end is connected in the jack of current transducer box, and the other end is connected in the four-core jack corresponding on the detector rear panel.

The system principle design mainly is to launch around function and the performance demands design unit that integrated circuit possessed and was equipped with that this testing tool will be finished.It mainly is made of unit such as sensor circuit, sensing circuit, metering circuit, working powers.It constitutes block diagram as shown in Figure 3.The designing requirement of each unit is to finish its different separately function among the figure.

The sensor circuit design mainly is the seizure of finishing detent control power off signal.This also is to need one of two big technical barriers that solve in this subject study.We must will consider the detent of all kinds of power supply performances to some extent from the on-the-spot angle of using of crane to this.Detent power supply form used on crane has two types of AC and DCs.AC type AC380V and AC220V arranged, once-through type voltage-type and current mode arranged.Voltage-type be direct current DC110V and DC220V, current mode be tens amperes of direct currents to last kiloampere, therefore just must consider above various electric power thus supplied to the seizure of outage moment point.This just requires us must take all factors into consideration the character of detent power supply when the zero-time circuit is caught in design, will catch by the characteristics that its characteristic meets itself each different electrical power, and the form of design circuit as shown in Figure 4 in view of the above.

Can see that by figure various types of power supply forms need be passed through various dissimilar circuit conversion, but finally all are converted into the DC voltage form.And this unified DC voltage is wanted to follow and is executed the sudden change of excitation and undergo mutation outward, this sudden change is exactly the signal of detent outage moment point, it can form the starting point time signal of sensor circuit, the trigger pip that the needed control of testing tool that Here it is begins to count.

The design of sensing circuit mainly is to advance in the test macro round the signals collecting that slides of can be accurately, intactly reel being rotated to a certain direction.Detection for the downslide braking distance need be carried out according to the physical quantity of measurand and the requirement of measuring accuracy.The downslide braking distance is with length metering, and unit is mm, and its precision should be controlled on the 0.1mm level according to designing requirement.In braking procedure, when weight hangs over when hauling wire rope on the suspension hook and making reel roll rotation together downwards, reel began to stop after one section rotation is slided to having produced with respect to detent dead electricity moment, form one section and slide arc length, this section slides arc length and is reflected in critical field that its requirement can not surpass about 9～250mm on the suspension hook.According to the measuring accuracy requirement, we have selected revolution is the sensor of 6000 umber of pulses.In order to guarantee measuring accuracy, each pulse should be 0.1mm corresponding to the precision of arc length, and this is the direct precision with respect to cable drum.Because the multiplying power of lifting hook pulley group is present in 1 to 10 possibility, therefore be reflected to braking distance real on the suspension hook and also will remove in 1 to 10 coefficient, the minimum precision of this tester should be 0.1mm thus, corresponding raising is enough to the 250mm descending braking distance for the 9mm at suspension hook position along with the raising of lifting hook pulley group multiplying power.When the disk girth is designed to 600mm, then be equivalent to the arc length of 0.1mm once each pulse of circle 6000 umber of pulses, corresponding disk diameter should be 191mm.Therefore, the disk that with diameter is 191mm is associated in the sensor of 6000 pulses, assembly as the detecting instrument transducing part, to rotate coasting distance with disk near cable drum and send into sensing unit, carry out the processing of digital circuit then, can finally finish the surveying work that crane is glided and brakes.

The design of metering circuit mainly is to consider that how correct effectively that trigger pip is later effective impulse note, and converts thereof into pairing distance of glide or umber of pulse shows.Sensing circuit together with the design of metering circuit as shown in Figure 5.

Be connected disk on the sensor among Fig. 5 and arc length distance converted to the two ways of digital signals of the lead and lag that sensing circuit can export.Owing to this two paths of signals level is low unfavorable to back level processing, so be necessary to raise with the method for signal gain the grade of level, doing like this is to provide necessary condition for back level gauge length.In actual measurement, because there is elastic reaction in wire rope itself, the moment after detent stops the cable drum braking might produce the possibility that reel swings back and forth.This moment, the meter that adds up continuously that just might produce no both forward and reverse directions was long, so will increase measuring error greatly if adopt an independent way word signal to carry out gauge length.In order to overcome this problem, we adopt the method for leading, hysteresis two pulse signals as shown in the figure, and when prepulsing was ahead of the hysteresis pulse, metering circuit was only done plus coujnt; When prepulsing lagged behind the hysteresis pulse, metering circuit was only done the subtraction counting, and tending towards stability until swing rests on a certain numerical value.So just overcome reel swing back and forth the continuous folk prescription that caused to metering may, thereby guaranteed the correctness of test.Consider the randomness of the descent direction when sensor disk rotates near cable drum, if the supposition descent direction is for just at the scene, so just can be changed setting, so just be greatly facilitated on-the-spot test job by counting commutation button on the case front panel of device.

Error correct errors in printing design be consider since on the cable drum factor such as spiral-shaped of grooving designed to the measuring error that length metering produces.Make circular motion because sensor disk abuts against to follow on the reel to rotate together, and wire rope is the interior spirality of grooving that is coiled in reel, wire rope also is the spirality folding and unfolding when hoisting and descend.Because wirerope diameter and grooving width, in the folding and unfolding process existence of the length of run of the range ability of wire rope core center line and reel circumferential surface greater than, equal and less than three kinds of situations, consider the factor of grooving pitch simultaneously, it is also longer.Therefore, should take all factors into consideration the factor that these produce error during descending braking distance detects.And pulley block ratio just plays the relation of minification therein, and therefore correct descending braking distance L has extremely closely with these factors and concerns that it is their function, promptly L=f (φ, r, l, n) (wherein L is a descending braking distance; φ is a wirerope diameter; R is the grooving degree of depth; L is the grooving pitch; N is a pulley block ratio).If overcome these error components with hardware, will design a cover and can follow the hunting gear that grooving moves, but also must consider the factor of the grooving degree of depth, so just made the work complexity.In order to overcome this difficult problem, we have adopted the method that solves this problem by computer software.Work out the utilization software of " detection of crane descending braking distance " for this reason, thereby simplified work such as design, making greatly.We can utilize this software earlier before detection, input will detect specified lifting velocity, lifting mechanism wirerope diameter, the drum rope groove degree of depth, grooving pitch and the lifting mechanism pulley block ratio of crane, this software just can provide the specified distance of glide when braking under the rated condition, and this is the maximum permissible value of distance of glide just.Also can learn simultaneously pairing specified umber of pulse of distance of glide and downslide coefficient.So just can before detection, accomplish to know what's what, carry out testing with a definite target in view.When the measurement of reality, need only and instrument is set the downslide coefficient earlier, the distance of glide that just can obtain surveying in the measurement.

Complete machine structure design mainly is with easy to carry, simple to operately carries out for principle.Therefore consider the on-the-spot dirigibility that detects, uses, the power supply of detector is designed to the electric power storage form, for each unit provides enough power supplys.Before use as long as the sufficient accumulator electric energy of elder generation just can guarantee carrying out smoothly of test job during on-the-spot the detection.The casing design is divided into front and back panel.Front panel mainly is an operation part, and rear panel mainly is the importation.The design of complete machine cabinet as shown in Figure 7.

The braking distance of crane hoisting mechanism detent under the nominal load effect detects relevant national standard and has clearly defined test specification: to the suspension hook crane, (controller is in the stable operation of decline rate deep low gear for the braking distance of lifting thing when descending braking, after retracting zero-bit, the distance of glide when detent is powered down to weight and stops) should being not more than stable 1/65 of the distance that hoists in the 1min.Here include two main points, the one, the seizure of detent outage moment point; The 2nd, the measurement of distance of glide after this, so we must remove to research and develop this cover pick-up unit around these 2.Moment point seizure can obtain by inductor, the measurement of distance of glide then is will convert the slip arc length to by the pulse number that digital transducer corresponds to suspension hook weight distance of glide with the lifting mechanism cable drum to obtain, and its theory diagram as shown in Figure 1.

When considering that the interior suspension hook crane of present national standard scope is in lifting capacity is 250t, generally between 0.63～16m/min, the standard requirement is the lifting velocity of main hoisting mechanism: should be not more than stable 1/65 of the distance that hoists in the 1min to the braking distance of the specified weight of suspension hook crane loading when descending braking.In theory, the stable distance that hoists promptly can be considered specified lifting velocity in the 1min.In other words, 1/65 of specified lifting velocity is exactly the maximal value of the descending braking distance of crane.Therefore can converse 250t and should between 9.69～246mm, be about 9～250mm with the descending braking distance scope of interior crane main hoisting mechanism.Display precision for the descending braking distance lower limit 9mm of crane can satisfy test request more than 0.1mm; Its upper limit 250mm be if error control also can satisfy working condition requirement at 2.5mm with interior, so this device can reach 1% measuring accuracy and has practical significance.

In addition, we also must consider sensing device is moved with grooving track on the reel, so just can get rid of the measuring error that the drum rope groove degree of depth difference of different tonnages is brought, get rid of the measuring error that wirerope diameter brings with metering finishing coefficient, thereby improve the accuracy of systematic survey.

This detector has two kinds of trigger pip functions of voltage and current, and detent adopts the voltage triggered ratio shared with respect to current trigger will come much morely.But in some occasion, especially drive in the main hoisting mechanism of hoister in large tonnage at direct current motor, what often adopt is the DC brake of low-voltage and high-current.Look the difference of capacity motor, the working current of detent has tens amperes of situations about not waiting to last kiloampere.Just must finish and guarantee the reliably working of trigger circuit for this situation by the test and the test of testing laboratory.To this, no matter how many sizes of working current has, the light current form that we can become unified 4mA～20mA DC current to export the current conversion that differs in size by the form of current transducer, by the current signal isolated amplifier current conversion in this scope is become the output voltage of 0～5V then, thereby the big current transitions of finishing the prime current transducer is the manageable light current voltage of back stages of digital circuit.Their circuit connects as shown in Figure 6.

For the transmitter of 300A, according to the characteristic of himself, we seek the circuit parameter that the form that can simulate is debugged the back level in the laboratory.Input-output characteristic parameter for current transducer concerns just like following table one:

Table one:

Input current (A)	0.000	30.000	90.000	150.000	210.000	270.000	300.000
								Output current (mA)	4.01	5.53	8.745	11.965	15.17	18.385	19.995

Can list the relational expression of transmitter input and output according to the data in the above-mentioned table.

Because:

$k=\frac{y2-y1}{x2-x1}=\frac{19.995-4.01}{300.000-0.000}=0.05328$

So have:

y＝4.01+kx＝4.01+0.05328x

Wherein: x-represents the electric current (A) of transmitter input end;

Y-represents the electric current (mA) of transmitter output terminal;

The functional relation of the correspondence that table provided on Here it is.It is helpful in the working condition of laboratory simulation circuit analysis current signal isolated amplifier to us.

In order to seek the current signal isolated amplifier can promote back level gate circuit under which kind of situation action, we insert an adjustable stabilized voltage supply in amplifier input terminal, mimic channel through the current-limiting resistance composition, reach the variation of pair amplifier input end electric current 4mA～20mA with the size of regulating the source of stable pressure output voltage, the adjustable resistance W4 of pair amplifier changes therebetween, observes its situation that influences to final counter.We are summarized in following table two to test situation: table two:

Input current I Go into(mA)	Current detecting D2	Current trigger D3	Counter status	Adjustable resistance W4 (k Ω)
					4	Bright	Bright	Count enable	196.2
≥8	Brighter	Go out	Not count enable	196.2
					≥9	Brighter	Go out	Not count enable	134.4
≥10.73	Brighter	Go out	Not count enable	83.6

We can draw as drawing a conclusion by pair amplifier from last table by test:

(1) when amplifier input terminal only provides the electric current of 4mA, be serially connected in that its current in loop detects light emitting diode D2 and current trigger counting control gate level indication light emitting diode D3 is all lighted, counter is in the count enable state.

The input current of correspondence was 0A when the table of comparisons one can be seen 4mA, and promptly detent is in off-position.

(2) when the voltage of regulating source of stable pressure, when providing the electric current of 8mA to amplifier input terminal, D2 is brighter for the current detecting light emitting diode, current trigger counting control gate level indication light emitting diode D3 extinguishes, counter is in can not count status, illustrate that counter is blocked, be equivalent to detent and switch on.

(3) when the resistance of the external variohm of resonance-amplifier diminishes, make the electric current of the amp.in that current trigger counting control gate level indication light emitting diode D3 extinguishes improve, during corresponding 134.4k is 9mA, 83.6k the time be 10.73mA, being equivalent to the electric current that current transducer can turn-off counter works is increasing, and just requires the working current of detent increasing.

(4) when the resistance of the external variohm of determining amplifier is 196.2k, the input end of pair amplifier provides the analog current of 8mA, this moment, current detecting light emitting diode D2 was brighter, current trigger counting control gate level indication light emitting diode D3 extinguishes, counter just in time is in can not count status, illustrate that counter is blocked, be equivalent to detent working current at this moment and just in time play the effect of blocking counter works.The blockade electric current of this moment can be tried to achieve by above-mentioned function formula.

Because the current transducer input with the functional relation of output is

y＝4.01+kx＝4.01+0.05328x

Can try to achieve the value of x by transformation for mula corresponding to y.Promptly

$x=\frac{y-4.01}{0.05328}$

When known y=8mA, then have:

$x=\frac{y-4.01}{0.05328}=\frac{8-4.01}{0.05328}=74.88\left(A\right)$

This expression is when the detent working current of selecting during greater than 74.88A, and follow up amplifier could be worked, and counter could stop to count when detent is switched on, and counts during dead electricity.

(5) choose reasonable of current transducer.The detent working current that counter can not be counted is 74.88A, and the full scale span of transmitter is 300A, and the number percent that takes range is 24.96%, is about 25%.In other words, the working current of detent must be greater than the full scale value of current transducer 25%.The full scale of transmitter must be less than 4 times of detent working current in other words.For the transmitter of 300A, require the working current of detent to be not less than 75A, so 400A detent electric current is enough to make the flip-flop number circuit to be worked reliably.

To the rating test of descending braking distance detector, be after having adjusted counter, to carry out.At a diameter is on the rotary wheel surface of 315.5mm, marks a straight line that is parallel to the axle center with draw point.The sensor of loading onto rotating disk is fixed, rotating disk is abutted against on the rotor wheel, rotate wheel gently, pointer is aimed at this straight line, instrument is carried out clear operation.One week of uniform rotation wheel is aimed at straight line once more up to pointer, notes reading on the tester; The reading of noting in a week on the tester is returned in same operation.Positive and negative respectively carrying out ten times, all read-record sees the following form:

Unit: pulse

Number of times	The pulse reading is just circling	Return all pulse readings	Absolute error is just circling	Return all absolute errors
					1	9911	-9913	-0.75	-1.25
2	9913	-9910	1.25	1.75
					3	9910	-9911	-1.75	0.75
4	9914	-9913	2.25	-1.25
					5	9910	-9912	-1.75	-0.25
6	9909	-9911	-2.75	0.75
					7	9912	-9910	0.25	1.75
8	9911	-9913	-0.75	-1.25
					9	9913	-9911	1.25	0.75
10	9914	-9912	2.25	-0.25

On average

9911.7

-9911.6

-0.05

0.15

By calculating the circumference that can obtain the 315.5mm diameter be:

C=315.5 * 3.1416=991.1748 (mm) gets 991.175mm.Because 0.1mm is corresponding to 1 umber of pulse, so 991.175mm should be corresponding to 9911.75 umber of pulses.Can see that the average pulse number that is just circling is 9911.7 from table, its absolute error is-0.05 pulse, is equivalent to-the 0.005mm error; The average pulse number that returns a week is-9911.6, and its absolute error is 0.15 pulse, is equivalent to the 0.015mm error, and these all are the error of measured value with respect to theoretical value.0.7 pulse may be counted 1 umber of pulse in actual metered, also might count 0 umber of pulse, a pulse in like manner-0.6 may be counted-1 umber of pulse, also might count 0 pulse, so real measuring error should be ± 1 umber of pulse, should be between ± the 0.1mm corresponding to circular arc length.The measurement average error that this shows this instrument depends on the quantization error of digital quantity.

The measurement display precision of detector depends primarily on the display precision of counter.The indication range of technical performance index indication display is between-19999～99999.Its decimal place can be set between 0.0000～00000 (five integers), for the descending braking distance 9mmm in the measurement standard scope between the 250mm, the decimal place that instrument shows can be set at 00.000 and 000.00, the measurement display precision scale that this shows instrument can be adjusted on 3 or 2 as required, it is than measuring accuracy 1% high last 2 to 1 orders of magnitude of the initial proposition of this project, so measuring accuracy can be guaranteed fully.

Gordian technique of the present invention is:

1, the starting point of braking distance---detent power-cut time is exactly the starting point of braking beginning.In order to guarantee the security performance of on-the-spot crane, we have proposed carrying out the on-the-spot requirement that detects on the spot not dismantling any parts, device with crane, therefore we must and convert the relative trigger signal to the induction of detent power off signal, make the length metering device can receive the signal that begins to count.

2, the record of braking distance---lifting mechanism is when the stable operation of decline low speed, and detent just should cut off the power supply automatically when operator's joystick is got back to zero-bit.Because the physical construction transmission of detent needs a process, just can make the detent band-type brake touch braked wheel and embrace, this transient process is exactly the response process of detent.Owing to there is the transient process in this response, make the weight on the suspension hook to fall downwards, because the traction of wire rope and the machinery inertial of the gear train that hoists itself, caused and under the rated load action of gravity, produced cable drum rolling slippage, arrive suspension hook by wire rope transfers, thereby formed the corresponding distance that moves down.We can represent rolling distance by the digital sensing technology with the arc length pulse signal for this reason, thereby just can solve the problems of measurement of downslide braking distance.

Beneficial effect

The present invention is custom-designed for the detection of overhead travelling crane elevating mechanism descending braking distance, and it has provided the possibility of quantitative test to the adjustment of detent.The present invention can adjust detent is single, makes each stressed index both reach national safety standard, again can be balanced, be tending towards mean allocation during overall operation.In addition, utilizing this device can also expand physical quantitys such as the coasting distance of the various travelling mechanisms of the hoisting machinery (as trestle crane, electric single beam crane, electric single-beam underhung crane, runabout crane etc.) to other form, speed detects, be all manufacturers' relevant with hoisting machinery product export check, the work for inspection of installation, maintenance, maintenance unit, applying unit and inspection body unit provides professional means of testing.

The present invention can choose reasonable test the position, makes full use of sensor technology, the braking distance when accurately measuring the decline of lifting mechanism weight.For the complete machine performance of crane is examined, type approval test is examined and provide a kind of quantitative proving installation in the security performance check with crane, be that the braking ability and the adjusting situation thereof of assessment detent proposes scientific basis.

Description of drawings

Fig. 1 is the utility model schematic diagram.

Fig. 2 is the utility model formation picture of device.

Fig. 3 is system's pie graph.

Fig. 4 is the sensor circuit block diagram.

Fig. 5 is sensor circuit and metering circuit block diagram.

Fig. 6 is a current triggering circuit.

Fig. 7 is complete machine cabinet figure.

Among Fig. 7: 1-counting display window 2-power switch locking press button 3-power light 4-power supply capacity button 5-power supply capacity pilot lamp 6-voltage triggered locking press button 7-voltage triggered pilot lamp 8-current trigger locking press button 9-current trigger pilot lamp 10-current detecting pilot lamp 11-reel signal 1 lamp 12-reel signal 2 lamp 13-tracer signals 1 lamp 14-tracer signal 2 lamp 15-counting commutation locking press button 16-counting locking locking press button 17-reset button

Embodiment

Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiment only to be used to the present invention is described and be not used in and limit the scope of the invention.Should be understood that in addition those skilled in the art can make various changes or modifications the present invention after the content of having read the present invention's instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.

This device mainly is made of unit such as sensor circuit, sensing circuit, metering circuit, working powers.It constitutes block diagram as shown in Figure 3.The designing requirement of each unit is to finish its different separately function among the figure.

Sensor circuit mainly is the seizure of finishing detent control power off signal.Detent power supply form used on crane has two types of AC and DCs.AC type AC380V and AC220V arranged, once-through type voltage-type and current mode arranged.Voltage-type be direct current DC110V and DC220V, current mode be tens amperes of direct currents to last kiloampere, therefore just must consider above various electric power thus supplied to the seizure of outage moment point, the form of its circuit as shown in Figure 4.

Can see that by figure various types of power supply forms need be passed through various dissimilar circuit conversion, but finally all are converted into the DC voltage form.And this unified DC voltage is wanted to follow and is executed the sudden change of excitation and undergo mutation outward, this sudden change is exactly the signal of detent outage moment point, it can form the starting point time signal of sensor circuit, the trigger pip that the needed control of testing tool that Here it is begins to count.

Sensing circuit mainly is to advance in the test macro round the signals collecting that slides of can be accurately, intactly reel being rotated to a certain direction.The disk that with diameter is 191mm is associated in the sensor of 6000 pulses, assembly as the detecting instrument transducing part, to rotate coasting distance with disk near cable drum and send into sensing unit, carry out the processing of digital circuit then, can finally finish the surveying work that crane is glided and brakes.

Metering circuit mainly is that the effective impulse that trigger pip is later is noted, and converts thereof into pairing distance of glide or umber of pulse shows.Sensing circuit together with the design of metering circuit as shown in Figure 5.

Be connected disk on the sensor among the figure and arc length distance converted to the two ways of digital signals of the lead and lag that sensing circuit can export.Owing to this two paths of signals level is low unfavorable to back level processing, so be necessary to raise with the method for signal gain the grade of level, doing like this is to provide necessary condition for back level gauge length.In actual measurement, because there is elastic reaction in wire rope itself, the moment after detent stops the cable drum braking might produce the possibility that reel swings back and forth.This moment, the meter that adds up continuously that just might produce no both forward and reverse directions was long, so will increase measuring error greatly if adopt an independent way word signal to carry out gauge length.In order to overcome this problem, we adopt the method for leading, hysteresis two pulse signals as shown in the figure, and when prepulsing was ahead of the hysteresis pulse, metering circuit was only done plus coujnt; When prepulsing lagged behind the hysteresis pulse, metering circuit was only done the subtraction counting, and tending towards stability until swing rests on a certain numerical value.So just overcome reel swing back and forth the continuous folk prescription that caused to metering may, thereby guaranteed the correctness of test.Consider the randomness of the descent direction when sensor disk rotates near cable drum, if the supposition descent direction is for just at the scene, so just can be changed setting, so just be greatly facilitated on-the-spot test job by counting commutation button on the front panel.

Error correct errors in printing design be consider since on the cable drum factor such as spiral-shaped of grooving designed to the measuring error that length metering produces.Make circular motion because sensor disk abuts against to follow on the reel to rotate together, and wire rope is the interior spirality of grooving that is coiled in reel, wire rope also is the spirality folding and unfolding when hoisting and descend.Because wirerope diameter and grooving width, in the folding and unfolding process existence of the length of run of the range ability of wire rope core center line and reel circumferential surface greater than, equal and less than three kinds of situations, consider the factor of grooving pitch simultaneously, it is also longer.Therefore, should take all factors into consideration the factor that these produce error during descending braking distance detects.And pulley block ratio just plays the relation of minification therein, and therefore correct descending braking distance L has extremely closely with these factors and concerns that it is their function, promptly L=f (φ, r, l, n) (wherein L is a descending braking distance; φ is a wirerope diameter; R is the grooving degree of depth; L is the grooving pitch; N is a pulley block ratio).If overcome these error components with hardware, will design a cover and can follow the hunting gear that grooving moves, but also must consider the factor of the grooving degree of depth, this is a very complex engineering.In order to overcome this difficult problem, we have adopted the method that solves this problem by computer software.Work out the utilization software of " detection of crane descending braking distance " for this reason, thereby simplified work such as design, making greatly.We can utilize this software earlier before detection, input will detect specified lifting velocity, lifting mechanism wirerope diameter, the drum rope groove degree of depth, grooving pitch and the lifting mechanism pulley block ratio of crane, this software just can provide the specified distance of glide when braking under the rated condition, and this is the maximum permissible value of distance of glide just.Also can learn simultaneously pairing specified umber of pulse of distance of glide and downslide coefficient.So just can before detection, accomplish to know what's what, carry out testing with a definite target in view.When the measurement of reality, need only and instrument is set the downslide coefficient earlier, the distance of glide that just can obtain surveying in the measurement.

This detector complete machine cabinet as shown in Figure 3, front and back panel all has arrangement separately.Front panel mainly is an operation part, and rear panel mainly is the importation.The physical dimension of detector cabinet: 300mm * 180mm * 160mm.

Front panel consists of the following components:

(a) display window---the high-speed counter by finished product constitutes counting.Be detected the coasting distance of reel or the umber of pulse of correspondence after being used for showing the detent outage.

(b) power switch locking press button---the power supply when being used for controlling the work of this detector, pressing self-locking is energized.

(c) power light---power light is bright when power switch is pressed power supply and is switched on.

(d) power supply capacity button---when pressing primary power source capacity button, the power supply capacity pilot lamp can show the capacity situation of detector internal cell storage.

(e) power supply capacity pilot lamp---show the situation of current detection instrument internal cell capacity storage, form by four lamps.One of high order end is red, represents and must charge when bright separately.Three of all the other right-hand members are green.Four complete represents the power supply abundance when bright, and the power supplys that from left to right light three, two expression storages are according to this weakening.

(f) whether voltage triggered locking press button---it is normal to check triggering control to press this button when the selector switch on the rear panel places voltage location.

(g) voltage triggered pilot lamp---the voltage triggered pilot lamp is bright when the selector switch on the rear panel places voltage location.The voltage triggered pilot lamp goes out when the voltage triggered locking press button is pressed, and it is normal that expression triggers control.The voltage triggered pilot lamp also goes out when detent is switched on.

(h) whether current trigger locking press button---it is normal to check triggering control to press the current trigger locking press button when the selector switch on the rear panel places Current Position.

(i) current trigger pilot lamp---the current trigger pilot lamp is bright when the selector switch on the rear panel places Current Position.The current trigger pilot lamp goes out when the current trigger locking press button is pressed, and it is normal that expression triggers control.The current trigger pilot lamp also goes out when detent is switched on.

(j) current detecting pilot lamp---when the selector switch on the rear panel places Current Position, and insert on the current detecting socket of plate in the back current trigger with current inductor after, the current detecting pilot lamp is bright, the expression inductor is switched on.

(k) reel signal 1 lamp---expression is sent into the flicker expression from the first via detection signal of reel sensor.

(l) reel signal 2 lamps---expression is sent into the flicker expression from the second road detection signal of reel sensor.Signal 1 and signal 2 differ 90 degree on circuit.

(m) tracer signal 1 lamp---expression has been sent into input end of counter from the pulse of reel signal 1.

(n) tracer signal 2 lamps---expression has been sent into No. two input ends of counter from the pulse of reel signal 2.Tracer signal 1 lamp and tracer signal 2 lamps extinguish simultaneously when pressing voltage triggered or current trigger locking press button, represent that two paths are working properly.

(o) counting commutation locking press button---because counter has positive and negative Presentation Function, supposition just drops in the ordinary course of things, rises to negatively, switches to the supposition situation with this button at an easy rate in test site so.

(p) counting locking locking press button---be to keep accurately can the count value maintenance being locked of data after the downslide braking distance has detected, in order to avoid change with this locking press button.

(q) reset button---when reel when descending one grade of stable operation, must the value on the counter be removed with reset button, return braking distance after zero to guarantee to measure exactly detent.

Rear panel consists of the following components:

1. selector switch---the control form of power according to detent is selected.Just expression comes flip-flop number with voltage when being selected in " voltage ", and just expression comes flip-flop number with electric current when being selected in " electric current ".

2. voltage change-over switch---because internal integrated circuit is to the requirement of input voltage, be " voltage triggered 1 " so alternating current 220V～380V and direct current 220V are summed up one grade, it is " voltage triggered 2 " that direct current 110V sums up another shelves.

3.AC220V～380V DC220V voltage triggered 1 jack---when the control voltage of confirming detent is AC220V～380V or DC220V, just can insert the jack of voltage triggered 1 with the three-pin plug on the two core connecting lines, two clips of the other end are clamped any two connection terminals of detent control voltage.

4.DC110V voltage triggered 2 jacks---when the control voltage of confirming detent is DC110V, can insert the jack of voltage triggered 2 with the three-pin plug on the two core connecting lines, two clips of the other end are clamped two connection terminals of detent control voltage.

5. current trigger jack---when confirm detent be controlled to be current forms the time, just can seal in the detent umbilical cable in the current transducer of the other end with the insertion of the four eyed plug on the four-core connecting line.

6. the reel sensor jack---after sensor disk was good by the support fixed in position, five plugs of an end of available five core connecting lines inserted disc sensor, and the other end inserts on the reel sensor jack.

7. the charger power supply---when front panel power supply capacity pilot lamp red light was bright, the charger that can pass through configuration was to the charging of this tester.

Before carrying out the detection of overhead travelling crane descending braking distance, earlier record the grooving width and the degree of depth on wirerope diameter, the lifting mechanism reel with vernier caliper, cooperation or knotmeter with stopwatch and ruler record specified lifting velocity, with visual observation lifting hook pulley group multiplying power number.These data are sent in the data input field on " detection of crane descending braking distance " special software page, after pressing sub-screen below " specified downslide pulse is calculated " button, " downslide coefficient calculations " button and " specified descending braking distance calculating " button then, just can in the data Output bar, demonstrate the value of " specified umber of pulse ", " downslide coefficient " and " specified descending braking distance number " respectively." downslide coefficient " value is wherein inserted it in preset proportion PS.AX item by the operation to count display on the detector, and the scaling position of selected good dp item displayed value is the ready work of ensuing detection.According to the kind of detent working power, select the connecting line of voltage or current trigger.If voltage is then selected three core connecting lines for use, the clip on the one end is clamped two power connection end in the detent terminal box, other end socket inserts in three corresponding on the detector rear panel core jacks; If big electric current is then selected the four-core connecting line for use, an end is connected in the jack of current transducer box, and the other end is connected in the four-core jack corresponding on the detector rear panel.Open the upper semi-circle of current transducer earlier, entangle detent service cable bonnet and tightly screw on.The sensor that has disk is fixed on the gauge stand support bar, makes disk abut against the smooth periphery of rope drum place, the magnetic switch of screwing on fixes gauge stand.As measuring rotating speed, grasp disc sensor, push the reel side gently to.Notice driver control lifting mechanism by counting commutation button, does not have "-" number (be+number) before the numeral on the display when adjusting reel and descending.Follow reel when rotating together when the disk on the sensor, press the reset button on the front panel, the display zero clearing.When handle was got back to zero-bit from keeping out, display will demonstrate the distance that the reel rotation is moved in the braking procedure the operation driver, the descending braking distance value of Here it is lifting mechanism hook.For zero load or load, operation all is the same, and just the value that shows is different.Certainly, also can adopt the umber of pulse of measuring the descending braking distance correspondence earlier, but the preset proportion PS.AX item of this moment will be set to 1, the dp item is made as integer, and remaining measures same as above getting final product.Then the umber of pulse that records is inputed to software for calculation together with wirerope diameter and grooving parameter, just can obtain comprising all numerical value of actual descending braking distance in " detection of the crane descending braking distance " below of the special software page.

The measurement display precision of this detector depends primarily on the display precision of counter.The indication range of technical performance index indication display is between-19999～99999.Its decimal place can be set between 0.0000～00000 (five integers), for the descending braking distance 9mmm in the measurement standard scope between the 250mm, the decimal place that instrument shows can be set at 00.000 and 000.00, the measurement display precision scale that this shows instrument can be adjusted on 3 or 2 as required, it is than measuring accuracy 1% high last 2 to 1 orders of magnitude of the initial proposition of this project, so measuring accuracy can be guaranteed fully, their display precision is ± 1 word.

Claims (9)

1. descending braking distance of bridge crane hoisting mechanism pick-up unit comprises:

Detent outage inductor: induction detects detent control power cut-off formed trigger pip of moment;

Digital transducer: the pulse signal that contacts and send with cable drum;

Measuring apparatus: acceptance is also measured from the sensor pulse signal after the trigger pip and is shown;

The error device of correcting errors in printing: get rid of the measuring error of bringing by grooving width, the grooving degree of depth and wirerope diameter.

2. a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit according to claim 1 is characterized in that:

Described detent outage inductor is composed in series by detent power supply, electric energy inductor, signal processor, level trigger.

3. a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit according to claim 1 is characterized in that:

Described digital transducer is composed in series by sampling roller, digital sensor, the long transmitter of two-phase arteries and veins, signal gain device.

4. a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit according to claim 1 is characterized in that:

Described measuring apparatus comprises length measuring and range display.

5. a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit according to claim 1 is characterized in that:

Inner being equipped with of described device can guarantee the normal accumulator that uses.

6. a kind of descending braking distance of bridge crane hoisting mechanism pick-up unit according to claim 1 is characterized in that:

The housing face-plate of described device comprises:

(a) display window---the high-speed counter by finished product constitutes counting; Be detected the coasting distance of reel or the umber of pulse of correspondence after being used for showing the detent outage;

(b) power switch locking press button---the power supply when being used for controlling the work of this detector, pressing self-locking is energized;

(c) power light---power light is bright when power switch is pressed power supply and is switched on;

(d) power supply capacity button---when pressing primary power source capacity button, the power supply capacity pilot lamp can show the capacity situation of detector internal cell storage;

(e) power supply capacity pilot lamp---show the situation of current detection instrument internal cell capacity storage, form by four lamps;

One of high order end is red, represents and must charge when bright separately; Three of all the other right-hand members are green; Four complete represents the power supply abundance when bright, and the power supplys that from left to right light three, two expression storages are according to this weakening;

(f) whether voltage triggered locking press button---it is normal to check triggering control to press this button when the selector switch on the rear panel places voltage location;

(g) voltage triggered pilot lamp---the voltage triggered pilot lamp is bright when the selector switch on the rear panel places voltage location;

The voltage triggered pilot lamp goes out when the voltage triggered locking press button is pressed, and it is normal that expression triggers control; The voltage triggered pilot lamp also goes out when detent is switched on;

(h) whether current trigger locking press button---it is normal to check triggering control to press the current trigger locking press button when the selector switch on the rear panel places Current Position;

(i) current trigger pilot lamp---the current trigger pilot lamp is bright when the selector switch on the rear panel places Current Position;

The current trigger pilot lamp goes out when the current trigger locking press button is pressed, and it is normal that expression triggers control; The current trigger pilot lamp also goes out when detent is switched on;

(j) current detecting pilot lamp---when the selector switch on the rear panel places Current Position, and insert on the current detecting socket of plate in the back current trigger with current inductor after, the current detecting pilot lamp is bright, the expression inductor is switched on;

(k) reel signal 1 lamp---expression is sent into the flicker expression from the first via detection signal of reel sensor;

(l) reel signal 2 lamps---expression is sent into the flicker expression from the second road detection signal of reel sensor;

Signal 1 and signal 2 differ 90 degree on circuit;

(m) tracer signal 1 lamp---expression has been sent into input end of counter from the pulse of reel signal 1;

(n) tracer signal 2 lamps---expression has been sent into No. two input ends of counter from the pulse of reel signal 2; Tracer signal 1 lamp and tracer signal 2 lamps extinguish simultaneously when pressing voltage triggered or current trigger locking press button, represent that two paths are working properly;

(o) counting commutation locking press button---because counter has positive and negative Presentation Function, supposition just drops in the ordinary course of things, rises to negatively, switches to the supposition situation with this button at an easy rate in test site so;

(p) counting locking locking press button---be to keep accurately can the count value maintenance being locked of data after the downslide braking distance has detected, in order to avoid change with this locking press button;

(q) reset button---when reel when descending one grade of stable operation, must the value on the counter be removed with reset button, return braking distance after zero to guarantee to measure exactly detent.

7. a kind of descending braking distance of bridge crane hoisting mechanism detection method according to claim 1 comprises the following steps:

(1) records the grooving width and the degree of depth on wirerope diameter, the lifting mechanism reel with vernier caliper, record specified lifting velocity, with visual observation lifting hook pulley group multiplying power number, with these data error originated from inputs device of correcting errors in printing with the cooperation or the knotmeter of stopwatch and ruler;

(2) the complete machine screen will show the value of " specified umber of pulse ", " downslide coefficient " and " specified descending braking distance number ",

" downslide coefficient " value is wherein inserted in the preset proportion PS.AX item scaling position of selected good dp item displayed value;

(3), select the connecting line of voltage or current trigger according to the kind of detent working power;

(4) open the upper semi-circle of current transducer, entangle detent service cable bonnet and tightly screw on; The sensor that has disk is fixed on the gauge stand support bar, makes disk abut against the smooth periphery of rope drum place, the magnetic switch of screwing on fixes gauge stand;

(5) follow reel when rotating together when the disk on the sensor, press the reset button on the front panel, the display zero clearing;

When handle was got back to zero-bit from keeping out, display will demonstrate the distance that the reel rotation is moved in the braking procedure, i.e. the descending braking distance value of lifting mechanism hook.

8. a kind of descending braking distance of bridge crane hoisting mechanism detection method according to claim 7 is characterized in that:

Described step (2) adopts the umber of pulse of descending braking distance correspondence, and its preset proportion PS.AX item is set to 1, and the dp item is made as integer.

9. a kind of descending braking distance of bridge crane hoisting mechanism detection method according to claim 7 is characterized in that:

Described step (3) if in voltage, then select three core connecting lines for use, the clip on the one end is clamped two power connection end in the detent terminal box, other end socket inserts in three corresponding on the detector rear panel core jacks; If big electric current is then selected the four-core connecting line for use, an end is connected in the jack of current transducer box, and the other end is connected in the four-core jack corresponding on the detector rear panel.

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