CS241604B1 - Device for automatic scanning of non-planarity and saberiness of workpiece - Google Patents

Abstract

The device is intended for sensing the unevenness and saberness of the workpiece, when these values are not sufficiently known and when it is necessary to superimpose the CNC program on this curvature. It consists of a measuring quill fixed by a carrier to the machine spindle and at its working end equipped with a contact roller rollingly mounted in the sensor body and pressed against the edge of the workpiece by a pneumatic cylinder and carrying a toothed measuring comb which is in engagement with the pinion of the rotary incremental sensor, while the beginning of the working stroke is defined by a limit switch controlled by a stop adjusted on the measuring quill.

Description

The invention relates to a device for the automatic detection of workpiece flatness and saberity, which are not known in advance and when the CNC program has to be superimposed on this curvature »

Until now, this problem has been solved with a copying device, when the approach point, such as a groove, is switched to the feedback sensor from the machine itself to the measuring sensor of the copying device and the groove surface is machined.

After the groove is completed, the feedback must be switched back to the machine and manually approached the next starting point. Then the whole cycle is repeated. In another way, it is machined only by the machine itself and it is necessary to measure in detail the actual workpiece curvature, define mathematically the resulting trajectory, extrapolate it into individual blocks of the partprogram and enter it into the CNC program and execute it with the machine.

When using a photocopying machine, the resulting machining time is very long due to the lengthy manual approach and places great demands on the machine operator. The second method requires considerably long time for measuring the workpiece, high demands on qualification and operator at the measuring station and finally the technological preparation for the creation of own part program is also complicated.

The disadvantage of these disadvantages is substantially eliminated by the device for automatic sensing of flatness and saberity of the workpiece, which consists of a measuring quill fastened by the carrier to the headstock and provided at its working end with a contact roller mounted in the sensor body and pressed against the workpiece by a pneumatic cylinder. a toothed metering ridge engaging the pinion of the rotary incremental encoder, wherein the start of the working stroke is defined by a conical switch actuated by a stop provided on the measuring quill.

The advantage of the solution according to the invention is that there is no switching of the feedback from the transducer, the correction is used automatically by invoking the instructions from the part program. The device allows for accurate approach to the starting point for machining, even if this has not been precisely predetermined due to workpiece clamping or manufacturing inaccuracies. It enables to measure the workpiece curvature in a pre-selected plane in the measuring cycle of the CNC and save the values in the system table for further machining.

A practical embodiment of the device is shown schematically in the drawing.

As can be seen from the drawing, the device consists of a measuring quill J secured by a carrier 11 to the headstock 1. At the working end of the roller 2, the roller is mounted in the sensor body 2 and pressed against the workpiece edge 2 by a pneumatic cylinder. a toothed metering ridge 2 engaging the pinion of the rotary incremental encoder 8 and the beginning of the working stroke defined by the limit switch 2 controlled by the stop 10 when screwed to the measuring quill In a particular machine application, the toothed metering ridge 2 with the rotary incremental encoder 6 can be interchanged the essence has changed. The pneumatic cylinder can also be replaced, for example, by a spring-loaded cylinder.

The device forms a separate functional unit with a special access to the CNG system. After programming a special auxiliary function, the device allows to superimpose the interpolated path to an arbitrarily curved planar path in the machine direction of the machine tool portal. The change of the position of the headstock 1 to the programmed coordinate is indicated in the GNC system and after the operation the absolute position data of the coordinate are automatically corrected to the actual extent. Further, the properties of the sensor 8 enable a measuring cycle to accurately approach the edge of the inaccurately clamped workpiece 2 so that the spindle 1 with the free contact of the sensor moves to the programmed coordinate near the inaccurately determined edge. Then the measuring cycle begins, ie the touch and e is pressed and the CNG system evaluates in a special mode the zero line of the sensor 8 on the correction sensor. The exact position of the workpiece edge in relation to the headstock 2 is thus known. 0 This value automatically corrects the part program coordinates and starts machining the edge.

-3241 604 of a workpiece whose position has not been precisely predetermined to the machine zero.

Claims (1)

BEFORE THE INVENTION Device for automatic sensing of flatness and saberity of a workpiece, characterized in that it consists of a measuring quill (3) fastened by a support (11) to the headstock (1) and provided at its working end (13) with a contact roller (4) a sensor body (5) and pressurized to the workpiece edge (2) by a pneumatic cylinder, the measuring quill (3) being fitted with a toothed measuring ridge (7) engaged with the pinion (12) of the rotary incremental sensor (8), The working stroke is defined by a limit switch (9) controlled by a stop (10) provided on the measuring quill (3).