CN104526462B - Two-time clamping machining workpiece benchmark coincidence method - Google Patents

Abstract

A two-time clamping machining workpiece benchmark coincidence method includes the steps of selecting a straight line as a probe benchmark line in the workpiece machining sensitive direction; selecting two end points in the probe benchmark line as probe points; probing the two points with a probe to obtain actual coordinate values of the two points; building a right triangle through the two s probe points; calculating a workpiece deviation rotation angle in the built right triangle; compensating the deviation rotation angle to an original coordinate system to enable a new coordinate system to be consistent with the actual position of a workpiece. The two-time clamping machining workpiece benchmark coincidence method performs probe probing and calculation on the rotation angle deviation appearing in two-time clamping of the workpiece through a numerical control machining tool, completely coincides the secondary clamping machining coordinate system with an actual state of the workpiece through a numerical control machining program angle compensation method, solves the problem of the rotation angle deviation of the two-time clamping of the workpiece, is suitable for solving the technical problem that the positioning benchmark of the same workpiece can not be unified in the two-time forward and backward clamping, obtains the unified height of the benchmark of the two-time forward and backward clamping machining, achieves significant application results of the two-time forward and backward machining of workpieces, such as end walls of rail vehicles and floors, improves the machining accuracy of the workpiece from the manufacturing source and ensures the machining quality of the workpiece.

Description

The datum coincidence method of workpiece processed by a kind of clamping twice

Technical field

The present invention discloses a kind of method ensureing clamping datum coincidence twice in process, belongs to Machine Manufacturing Technology Field.

Background technology

When workpiece need twice clamping processing when, due to second clamping it is difficult to ensure that and first time clamping state complete Unanimously, so machining benchmark twice is difficult to overlap, and then machining accuracy is led to decline.Through research, the deviation of clamping is general twice Occur all in the form of straight line variation and corner deviation.Straight line variation can be resolved with traditional compensation method, but arrives Also there is no a kind of effective solution for corner deviation so far.

Content of the invention

It is an object of the invention to provide a kind of method of benchmark centering, solve theoretical position and physical location during secondary clamping The impact to machining accuracy for the corner deviation.

For achieving the above object, the present invention provides a kind of clamping twice to process the datum coincidence method of workpiece, and its feature exists In comprising the following steps：

（1）One straight line is chosen on workpiece as detection datum line；

（2）Choose two-end-point as sensing point on detecting datum line；

（3）Detect at 2 points with probe and obtain this 2 points of actual coordinate value；

（4）Construct right angled triangle by two sensing points；

（5）The workpiece deviation anglec of rotation is calculated in the right angled triangle of construction；

（6）Deviation corner is compensated in former coordinate system, makes new coordinate system consistent with workpiece physical location.

The inventive method is to carry out probe detection to the workpiece corner deviation that clamping occurs twice using numerical control machine tool Calculate, will be complete with the virtual condition of workpiece for Cutter coordinate system during secondary clamping by nc program angle compensation process Overlap, the corner offset issue solving workpiece clamping twice is it is adaptable to same workpiece positive and negative Set and Positioning twice benchmark can not Unified technical problem, makes the positive and negative machining benchmark high unity of clamping twice, as positive and negative in the part such as in rail vehicle headwall, floor Twice processing on achieve significant application effect, from manufacture source improve workpiece machining accuracy it is ensured that workpiece plus Working medium amount.

Brief description

Fig. 1 is to choose the step schematic diagram detecting datum line；

Fig. 2 is the step schematic diagram choosing sensing point；

Fig. 3 is by new and old coordinate system schematic diagram after angle of deviation rotation.

Specific embodiment

（1）With reference to Fig. 1, the physical location of workpiece when second clamping（Solid box）With theoretical position（Dotted line frame）Exist One deviation corner, this angle is the principal element leading to mismachining tolerance.AB line is chosen on workpiece as detection datum line；

（2）Choose A and B as sensing point on detecting datum line AB, the effect of this two points is for subsequent calculations deviation Corner provides data.The distance of two points will as far as possible far apart some, so can improve the corner deviation calculating Accuracy；

（3）Detect the actual coordinate value obtaining 2 points of AB, A point coordinates using lathe probe（X1,Y1）, B point coordinates（X2, Y2）；

（4）With reference to Fig. 2, cross A point and do the straight line parallel with X-axis, cross B point and do the straight line parallel with Y-axis, with 2 points of A, B and Article two, the intersection point construction right angled triangle ABC of straight line, A, B are two sensing points, and C is intersection point；

（5）In the triangle ABC of construction, obtain AC=X1-X2, BC=Y2-Y1, then included angle A BC is exactly required inclined Difference corner, application trigonometric function can calculate angle ∠ ABC=arctan (AC/BC), and wherein BC is the known of programming personnel's selection Distance, AC is exactly the actual deviation value between 2 points of A, the B detecting；

（6）With reference to Fig. 3, original coordinate system XY is carried out by angle rotation by numerical control program, the anglec of rotation is exactly the（5）Step In the misalignment angle ∠ ABC that calculates, obtain new Cutter coordinate system X'Y' after rotation it is ensured that new coordinate system X'Y' and work Part virtual condition is completely the same, as long as program under this postrotational new coordinate system during secondary operations just can accurately meet Drawing size, eliminates the impact to machining accuracy for the corner deviation.

Claims (1)

1. a kind of clamping twice processes the datum coincidence method of workpiece it is characterised in that comprising the following steps：

（1）One straight line is chosen on workpiece as detection datum line；

（2）Choose two-end-point as sensing point on detecting datum line；

（3）Detect at 2 points with probe and obtain this 2 points of actual coordinate value；

（4）Do the parallel lines of X-axis by one of sensing point, then do the parallel lines of Y-axis by another sensing point, this two The intersection point of straight line is intersection point, constructs right angled triangle by the intersection point of two sensing points and two straight lines；

（5）The workpiece deviation anglec of rotation is calculated in the right angled triangle of construction；

（6）Deviation corner is compensated in former coordinate system, makes new coordinate system consistent with workpiece physical location.