Synchronism is measured -- the measurement technique of time of calibration of economic machine tool

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The method that convention measures error of displacement of numerical control machine tool is a static state -- measuring removed machine to want to stop stability a few seconds every time, collect fixed position data next. To small span or the measurement that grow journey machine tool, this means the machine down time with quite considerable need. And same measurement, use uninterrupted synchronous data to collect, need a few minutes only. In fact, data collects uninterrupted synchronism to still can measure more places, provide more detail and province time. For example, if interval of every 25 millimeter wants to stop 5 seconds, 1, the axis of 250 millimeter is long and the time that 5 operations that make a round trip need above 50 minutes. In addition, the static state locates because geometrical dimension, slideway and structural tigidity are caused,the error is normally. And the error of dynamic fixed position that does not measure commonly is by servo parameter, resonance frequency and acceleration or decelerate are spent cause. In other words, because the machine tool stopped before collecting data, this omited servo or dynamic error. Theoretic contrail precision should be OK with dynamic displacement error the watch is improved, is not watch of static displacement error. To die manufacturer, this are particularly important, because must want,make sure mould antrum and the intricate geometry form that a variety of surfaces comprise are completely consistent. Displacement measures   of   of method     Michelson hair understood interferometer 1881. He won Nobel physics award for this 1907 later. Michelson interferometer makes light source with Bai Guang, used secure and portable illuminator. Michelson interferometer is used to all the time through computational interference stripe measure an interval or be apart from quite. As the invention of laser, helium neon laser of Chan Pin replaced Bai Guang to serve as illuminant, replaced flat looking glass with 2 pyramid prism. Helium neon of Chan Pin stimulates beam of light by a minute bundle implement cent becomes 2 bundles of light, half beam of light passes one portable pyramid prism, other in part reflexes the pyramid prism that secures. When coming back, 2 reflex beam of light is being divided bundle implement encounter. After all smooth road critically tone allows, this 2 encountering beam of light are interfered each other, produce interference stripe. With the stripe of photoelectricity detector computation of one small area. The intensity change of each cycle expresses the half wavelengh of journey of portable pyramid prism. If the wavelengh of foregone laser, journey of prism of so portable pyramid also can get accurately. The question of odd frequency interferometer is too sensitive to noise. Accordingly, cannot discern from inside shift electric noise or gain drift. Shuang Pin's interferometer uses the helium neon laser of a pair of frequency, frequency of one carrier wave arises after 2 different frequency beam of light mixes. Accordingly, the distance message that carry is with exchanging undee form is not dc weaveform type. The permanent magnet that the problem of double frequency interferometer is need ponderosity and nice optical element in order to stabilize laser frequency, maintain a polarization, the scattering light that makes return laser resonance antrum is decreased the smallest. Because this system volume is heavy, have many optical element, when be being measured accordingly, major machine tool needs to open machine bedspread. Laser much general straps much general of laser of   of   of calibration system   to strap calibration system to use one laser much general to strap displacement measuring instrument (LDDM) , this system combined Doppler effect and microwave radar technology, optical heterodyne technology. The positional information that LDDM used craft of light produced by electricity, optical heterodyne and phasic demodulator to get mobile pyramid. LDDM is to use one helium neon to stimulate illuminate of beam of light one illuminator will measure displacement. Be stimulated by catoptric when illuminator is mobile frequency of happening of beam of light changes. Because be reflexed to stimulate the phasic direct ratio of beam of light the position at illuminator, because this can be measured,get positional change. To LDDM, polarization and cover astigmatism are not a problem, also do not need rigid optical system. The mirror can thrust smooth way at will, simple illuminator can use reflection to stimulate beam of light to aleatoric angle. How to use laser much general to strap   of   of calibration system   to want calibration common or ball silk lever, one bit is put on the axis, lever of motor drive silk sparked positional sensor. Can collect quadruplet for example with 4 positions sensor the data that every turn. Positional sensor sends one TTL pulse to PCMCIA to get stuck with sparking data is collected. The key that collects data uninterruptedly is exterior trigger and data are collected spark with TTL pulse is synchronous, also collect data at the same time namely. The pitch error of the ball silk lever of the typical case that surveys with 4 positions sensor is every turn 0.

2 inches. Because this is on more than 20 inches silk lever,every inches can measure 20 data. In this example, heat expands the error is smaller than pitch error much. Want an axis of machine tool of calibration numerical control, lay laser head go up in lathe bed, illuminator or drone is found a place for be on main shaft. Adjust the laser calibration that stimulates beam of light and groovy static state parallel and main shaft euqally. But with normally every make a move should stop 5 seconds to go to terminus different all the time, it is OK to adjust main shaft adjust main shaft now from begin to move continuously all the time terminal and do not need any stopping. Positional sensor can be placed go up in ball silk lever or on the runner of ball silk lever. The trigger that is not a contact is secured in magnetism on. The razor blade of trigger places the runner in filar lever to go up. Runner every turn, spark signal is sent PCMCIA to get stuck in order to collect data. A few machine tools spark signal is the controller that comes from a machine tool or the output of coder. Every turn 4 spark the   of   of   of process of sketch map experiment of lever of silk of pulse calibration ball uses interface of PCMCIA of rate of one height data card and outside the Duopule of trigger the laser calibration system of series, with every second 10, 000 data rate keeps synchronism collects data. Sensor of temperature of atmosphere force transducer, air and material temperature sensor can compensate what wavelengh change brings automatically to measure an error, the heat of material expands the standard less than in laser system. The laser head of LDDM is put on working platform, and illuminator finds a place for go up in the main shaft of perpendicular machining center. A trigger that is not a contact is secured to be in one magnetism on lever, and spark bit is fixed go up in runner. Collect data with the notebook computer that contains high speed PCMCIA to get stuck. Get stuck the output of LDDM processor and PCMCIA join with one tailor-made cable, the signal of trigger receives LDDM processor repeatedly. In the entree sheet of LDDM software, button of 2-D time cardinal number uses amount to to be installed according to collecting. Rate of optional choose data, time-interval and outside trigger. The oldest rate is every second 5 meters, top data rate is every second 10, 000 data. From spark pulse numerates to displacement the data life between is less than 100 accept second. In the experiment, 2 laser head is placed part in Y axis direction 4.

25 inches (10.

8 centimeters) distance. Displacement data collects a method with groovy static data first, every 2 inches stop, whole journey 18 inches. The biggest error is 0.

02 inches, backlash 0.

005 inches. Install likewise next, and with pause ceaselessly the trigger outside synchronism collects displacement data. With 0.

2 inches interval, whole journey 19 inches, walked along at least 5 to collect data back and forth. Pause ceaselessly synchronism collected data of 2 LDDM displacement. The poor cost that passes 2 displacement error is divided be apart from in order to part, can calculate an angle error. The biggest angle error is 8.

5 arc second. The biggest read an error point-blank for 0.

00012 inches. The data phase that collects with the static state is compared, the result of the data that synchronism collects is similar, but possess more detailed information. Go compensating the error of the machine tool with this displacement data, the data compensatory result that should collect than groovy static state is better. In addition, use synchronous data to collect OK and economic time, especially to small interval or large machine tool measuring is such more. CNC Milling