CN100436051C - Speed variation control method for high speed grinding machine - Google Patents

Abstract

The present invention relates to a speed variation control method for a high speed grinding machine, which belongs to the technical field of ultraprecise mechanical processing. The known technique is that a grinding machine is started, a grinding device changes a rotating speed and directly improves the rotating speed to a formal grinding speed after the inertia is overcome, and the rotation of the grinding device stops after sustaining some time under the function of the inertia after the processing is finished and the machine is stopped. The machining accuracy can not be ensured, and the machining efficiency is low by utilizing the method. In the present invention, the change of the rotating speed of the grinding device is controlled in the initial and the ending stages of grinding processing, and the present invention is made to have courses of slow, fast and slow acceleration and deceleration. The present invention has the effect that the impact between the grinding device and the surface of a workpiece is lightened largely, a scar is prevented from appearing, and therefore, the machining accuracy and the machining efficiency are improved. The present invention can be applied to the grinding process of a high speed grinding machine and has surface grinding processing to workpieces of hard alloy, engineering ceramics, etc.

Description

Speed variation control method for high speed grinding machine

Technical field

What the present invention relates to is the technical scheme of a relevant high speed solid abrasives lapping technology grinding rate control, control speed of related movement between workpiece and the grinding tool by control grinding tool rotating speed, improve machining accuracy and efficient, belong to ultraprecise Machining Technology field.

Background technology

Using the working face of workpiece such as high speed solid abrasives lapping machined carbide alloy, engineering ceramics is a kind of existing technology, for improving working (machining) efficiency, generally all improves attrition process speed in the attrition process process as far as possible.See shown in Figure 1ly, because action of inertia, grinder is at a very short time t ₁In finish a speed-raising process, at this process acceleration a variation by little rapid increase is arranged also, attrition process speed remains on a higher value v afterwards ₁On, just a kind of high speed constant speed processing is at process t process time ₂After, finish processing and stop, be because action of inertia equally, reduction of speed rapidly in a very short time, negative acceleration are by reducing greatly rapidly, and moderating process continues long time at last, and the time that whole attrition process ending phase continues is t ₃

Summary of the invention

The problem that prior art exists is, because this class workpiece is higher to the attrition process required precision, directly grinding rate is carried to formal high speed, between grinding tool and workpiece, can produce and impact, the initial stage of grinding particularly, the surface of the work situation is relatively poor, and impact therebetween also can be compared fierceness, and this not only can cause finished surface more coarse, increase processing capacity, may reduce working (machining) efficiency on the contrary, but also can reduce the machining accuracy of workpiece, and damage grinding tool.If grinding rate remains on the lower numerical value, will reduce lapping efficiency greatly.In addition, the attrition process ending phase is freely carried out, and the duration is longer, has also reduced working (machining) efficiency.Therefore, the objective of the invention is to, explore a kind of grinding rate control mode, the change constant speed is speed change, when improving working (machining) efficiency, can also guarantee machining accuracy, so we have invented a kind of speed variation control method for high speed grinding machine.

The present invention realizes like this, in the attrition process incipient stage, the acceleration of artificial control grinding tool rotating speed increases from slow to fast from zero, be raised to a half of formal grinding rate when the grinding tool rotating speed, a flex point appears in the variation of acceleration, the acceleration of control grinding tool rotating speed is reduced from fast to slow by maximum, reaches formal grinding rate up to the grinding tool rotating speed, and the acceleration of grinding tool rotating speed reduces to zero.

Based on same idea, in the attrition process ending phase, the negative acceleration of artificial control grinding tool rotating speed increases from slow to fast from zero, drop to a half of formal grinding rate when the grinding tool rotating speed, a flex point appears in the variation of acceleration, the negative acceleration of control grinding tool rotating speed is reduced from fast to slow by maximum, reduces to zero up to negative acceleration, and the grinding tool rotating speed also drops to zero.

Because the present invention is according to surface of the work situation difference in the process of lapping different phase, in the attrition process incipient stage or/and the attrition process ending phase is artificially controlled the raising of grinding tool rotating speed or/and reduce, and, acceleration also is a variable, further control the pace of change of acceleration targetedly, make the variation of situation of grinding tool change in rotational speed and surface of the work adapt, incremental, break-in gradually, this process continues time enough, alleviate the impact of grinding tool surface and surface of the work significantly, avoid artificial gash to occur, thereby improve machining accuracy.From whole process, also improved working (machining) efficiency, in other words, though time attrition process incipient stage prolong to some extent,, formal grinding rate can improve, the shortening that the time in formal process segment can be by a larger margin.In addition, the attrition process ending phase is artificially controlled reduction of speed, and is shorter than the time that inertia reduction of speed continues.

Description of drawings

Fig. 1 is prior art grinding rate and milling time change curve.Fig. 2 is the change curve of grinding rate of the present invention and milling time.Fig. 3 is that the present invention's technical conceive is applied to grind the curve of ending phase grinding rate along with the variation of milling time.

The specific embodiment

See shown in Figure 2ly, in the attrition process incipient stage, the acceleration of artificially controlling the grinding tool rotating speed increases from slow to fast from zero, and when the grinding tool rotating speed reaches a half of formal grinding rate, a flex point P appears in the variation of acceleration ₁, the acceleration of control grinding tool rotating speed reaches formal grinding rate v by maximum reducing from fast to slow up to the grinding tool rotating speed ₂, the acceleration of grinding tool rotating speed reduces to zero.The time that this attrition process incipient stage continues is t ₄, duration t that should the stage than prior art ₁Much longer, t ₁Be generally tens seconds, and t ₄Be a few minutes.But this moment is grinding rate v formally ₂Can be than v of the prior art ₁Height, the time t that the formal stage of attrition process continues ₅The time t that should the stage continues with prior art ₂Compare to some extent and shorten.

The climb curve of above-mentioned attrition process incipient stage of the present invention is made up of two parts, with flex point P ₁For symmetric points are the point symmetry state, a preceding part is following chord curve, and a back part is last chord curve.This curve can be the sine curve between 0～π, sees shown in Figure 2ly, and its formula is:

$v=\frac{v_2}{2}[1+\sin (t-\frac{\mathrm{\π}}{2})]$

This curve can also be the elliptic curve between 0～2a, sees shown in Figure 3ly, and its formula is:

$v=b(1-\sqrt{1-\frac{t^2}{a^2}})$ (0≤t≤a)

$v=b(1+\sqrt{1-\frac{{(t-2a)}^2}{a^2}})$ (a≤t≤2a)

Technical scheme according to the present invention, its attrition process ending phase reduction of speed process still can artificially be controlled, grinding rate control curve is that reduction of speed curve and the grinding rate of attrition process incipient stage control curve are that climb curve is the line symmetry status, see shown in Figure 3, line of symmetry is a straight line that is parallel to the v axle, and forward and backward two parts of this reduction of speed curve are with flex point P ₂For symmetric points are the point symmetry state, a preceding part is last chord curve, and a back part is following chord curve.The climb curve of shape and attrition process incipient stage is identical.According to the attrition process ending phase that this reduction of speed curve carries out, its duration is t ₆, it is still less than the duration t of prior art attrition process ending phase ₃This reduction of speed process also can alleviate the grinding tool that produces and the impact of surface of the work in the reduction of speed process, though the impact that this impact is produced in boosting velocity procedure is so big.Can consolidate or further improve the attrition process precision.

Claims (4)

1, a kind of speed variation control method for high speed grinding machine, attrition process has three phases, be incipient stage, formal stage and ending phase, incipient stage grinding tool raising speed rotation, formal stage grinding tool constant speed rotation, the rotation of ending phase grinding tool reduction of speed, it is characterized in that in the attrition process incipient stage, the acceleration of artificially controlling the grinding tool rotating speed increases from slow to fast from zero, when the grinding tool rotating speed is raised to a half of formal grinding rate, a flex point P appears in the variation of acceleration ₁, the acceleration of control grinding tool rotating speed is reduced from fast to slow by maximum, reaches formal grinding rate up to the grinding tool rotating speed, and the acceleration of grinding tool rotating speed reduces to zero.

2, speed variation control method for high speed grinding machine according to claim 1 is characterized in that, the climb curve of attrition process incipient stage is made up of two parts, with flex point P ₁For symmetric points are the point symmetry state, a preceding part is following chord curve, and a back part is last chord curve.

3, speed variation control method for high speed grinding machine according to claim 1, it is characterized in that, in the attrition process ending phase, the negative acceleration of artificial control grinding tool rotating speed increases from slow to fast from zero, when the grinding tool rotating speed drops to a half of formal grinding rate, a flex point P appears in the variation of acceleration ₂, the negative acceleration of control grinding tool rotating speed is reduced from fast to slow by maximum, reduces to zero up to negative acceleration, the grinding tool rotating speed also drops to zero, reduction of speed curve and climb curve are the line symmetry status, and line of symmetry is a straight line that is parallel to the v axle, and described v is a grinding rate.

4, speed variation control method for high speed grinding machine according to claim 3 is characterized in that, forward and backward two parts of reduction of speed curve are with flex point P ₂For symmetric points are the point symmetry state, a preceding part is last chord curve, and a back part is chord curve down, and the climb curve of the shape of this reduction of speed curve and attrition process incipient stage is identical.

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