The comparison of means of two kinds of 1 tap the machining center before for tap, it is the tap that chooses according to place and craft requirement commonly, in the be classified in machine program rotate speed of a main shaft is mixed / invert instruction, make up G74 of person G84 ／ to secure a loop again next, give out in fixed loop concerned data, among them the feed speed of Z axis is according to main shaft of × of F= tap pitch rotate speed reachs, such ability machine the screw that gives need to come. Although from apparently seeing main shaft rotate speed and feed rate cooperate to move according to pitch, but the rotational angle of main shaft is not controlled, and the feed of the angle position of main shaft and Z axis concerns without any synchronism, rely on constant main shaft rotate speed and feed speed merely cooperating is insufficient. The rotate speed of main shaft needs to experience to stop in the process of tap - turning - stop - invert - inactive process, main shaft should be quickened - apply the brake - quickly - apply the brake, plus what pledge as a result of workpiece material in cutting process inhomogenous, wave motion of main shaft load can make main shaft rate cannot constant changeless. To feed Z axis, its feed speed and main shaft also are similar, rate won't be constant, so both blend impossibly flawless. When this should use tap of this kind of means namely, must deserve to use contain bedspring the collet of adjustable device, will compensate the pitch error of Z axis feed and generation of campaign of main shaft corner with it. If we watch afore-mentioned tap processes carefully, see with respect to can apparent ground, when tap after all, z axis stopped and main shaft did not halt instantly (inertia) , tap bedspring collet is compressed a paragraph to be apart from, and when Z axis when back feed, main shaft is being quickened, pinchcock head by drawing, this kind of compensation made up for control means to be not worth the defect that cause, completed the treatment of tap. Not tall to precision requirement whorl aperture machines still OK and contented requirement with this kind of method, but taller to whorl precision requirement, the whorl of 6H or above and the material of the workpiece that be added are qualitative softer (copper or aluminium) when, whorl precision will cannot get assuring. Returning those who a bit want to notice is, when tap main shaft rotate speed is jumped over tall, z axis feed and pitch accumulate the error between the quantity bigger, the adjustable limits of pinchcock head also must enough big, as a result of the limitation of collet machinery structure, when using tap of this kind of means, main shaft rotate speed can be restricted only it is under 600r/min. Rigid tap puts forward in the light of the inadequacy of afore-mentioned means, it is added on main shaft installed positional coder, the angle position feedback that rotates main shaft accuses a system to form positional closed circuit to ability, establish synchronous relationship with Z axis feed at the same time, made sure main shaft corner coming back is spent and the line of dimension of Z axis feed gives birth to scale to concern strictly so. Because had this kind of synchronous concern, although the position of the angle as a result of the inertia, main shaft roll that adds slowdown time constant to different, load fluctuates and be caused or Z axis shift changes to also do not affect treatment precision, because give priority to axial corner and Z axis feed,be synchronous, in tap no matter any one party suffer interference happening to change, other one party also can change accordingly, maintain linear scale relationship forever. If we use rigid tap to machine whorl aperture, can very see clearly, when Z axis tap reachs the place, main shaft roll and Z axis feed are at the same time decelerate and at the same time inactive, main shaft inverts with Z axis back feed keeps consistent likewise. Had synchronous concern just about, tap collet is used it is OK to get collet or simpler special collet commonly, and when rigid tap, want cutting tool only (tap) intensity allows, the rotate speed of main shaft can rise a lot of, the main shaft speed of 4000r/min already be nothing difficult. Treatment efficiency raises 5 times above, whorl precision still gets assuring, had become a machining center is indispensable main function at present. The implementation of function of 2 rigid taps looks from electric pilot angle, numerical control system should have control of position of main shaft angle and synchronous function only, the machine tool can undertake rigid tap, still need to add the positional coder that holds point of view of feedback main shaft on the machine tool of course. Want to reflect the angle position of main shaft correctly, best a coder and connection of main shaft coaxial, when if construction of machinery of be confined to is necessary,passing transmission chain link, want to hold to 1:1transmission comparing, if use leather belt, asynchronous take cannot. Still one is plant likelihood, that is to be connected continuously between machine tool main shaft and main shaft electromotor namely, the in-house coder that can use itself of main shaft electromotor to take makes main shaft position feedback, save 2 expenditure. Outside the hardware with eliminate necessary installation, the design that main job is program of echelon graph control is debugged. There are a variety of numerical control systems on market, because manufacturer is different, be used to each different, to the signal of rigid tap arrangement and processing are completely different. The rigid tap that we once were designed and has debugged system of a few kinds of commonly used numerical control controls a process, trivaller. Debug personnel to understand echelon graph not easily to control a process, especially the first prototype debugs cycle to grow, go against popularize and use. Nevertheless, machining center had this function, enlarged size range of pipe bent, get the favour of the user. 3 need not design echelon graph to realize rigid tap to be in system of numerical control of FANUC Oi, parameter N0. If 5200#0 is by set 0, so rigid tap needs to be appointed with M code. Usually, we use M29, and also must design the ordinal program that answers relatively to it in echelon graph, this pair still has certain difficulty for the person that try the first time. Below normal circumstance, when doing not have special requirement, after initialization of main shaft parameter parameter No.
5200#0 set is 1, other is not moved basically about parameter, also need not add any new control programs, such much simpler. Moving in debugging, want to install rigid tap according to the physical characteristic of machine tool itself must a group of parameter () seeing a table. Process designing of instruction of fixed loop G84/G74 can be used directly after parameter has been installed, its format citing is as follows: Normal Align=center> watch is highest N0 of main shaft rotate speed.
5241 - N0.
The time constant N0 of 5244 main shaft and tap axis.
5261 - No.
N0 of gain of return of axis of 5264 rigid tap.
5280 - N0.
The limiting value N0 that deviation of position of shift of axis of the tap when 5284 rigid tap measures.
The limiting value N0 that deviation of position of shift of the main shaft when 5310 rigid tap measures.
The positional deviation when the tap axis when 5311 rigid tap stops measures limiting value N0.
The positional deviation when the main shaft when 5312 rigid tap stops measures limiting value Normal >N0.
Axis of Z of of of of of of of of of of G94; of of of right whorl of of process designing of 5313(1) minutely feed is minutely main shaft of of of Sl000; of of of M3 of feed is turning ( X-300 of G9OG84 of of 1000r/min) .
Y-250.
Z-150.
R-120.
Tap of P300F1000; right whorl, main shaft of of of Sl000; of of M4 of of of minutely feed of axis of Z of of of of of of of of G94; of of of left whorl of of pitch Lmm inverts ( X-300 of G9OG74 of of 1000r/min) .
Y-250.
Zl50.
R-120.
Tap of P300F1000; left whorl, pitch Lmm (2) every turn (main shaft) feed of axis of Z of of of of of of of G95; of of of right whorl of of feed process designing / main shaft every turn main shaft of of S1000; of of M3 is turning ( X-300 of G9OG84 of of 1000r/min) .
Y-250.
Z-150.
R-120.
P300F1.
Tap of 0; right whorl, feed of axis of Z of of of of of of of of G95; of of of right whorl of of pitch 1mm / main shaft every turn main shaft of of of S1000; of of M4 inverts (G90G74X-300 of of 1000r/min) .
Y-250.
Z150.
R-120.
P300F1.
Tap of 0; left whorl, process designing of tap of tigidity of above of of pitch Lmm because parameter No.
5200#0 setting is 1, fixed loop G84/ makes the statement of rigid tap, its process designing format is so complete as common as G84/G74 of former fixed loop tap is same. According to the use investigation of the user, rigid tap function greatly excel is common tap. CNC Milling
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