DE4432317B4 - Measuring device for cutting tools - Google Patents

Abstract

Device for measuring the cutting angle on rotary cutting tools, consisting of a receptacle (4) for the tool to be measured (5), a measuring slide carrier (7) on which a measuring slide (8) is guided in a longitudinally displaceable manner, at the end facing the tool (5) a measuring head (9) with a measuring sensor (10) is arranged, the measuring head (9) and the receptacle (4) for the tool (5) being able to be positioned and locked relative to one another, characterized in that the measuring head (9) for the measurement of the cutting edge angle of a rotating cutting tool, which is decisive for measuring the front and flank free angle, can be adjusted in different measuring directions.

Description

The invention relates to a device for measuring the cutting edge geometry of rotating cutting tools like milling and face milling cutters, consisting of a recording for one to be checked Tool, a measuring slide holder, on the a measuring slide longitudinal displacement guided is at the end facing the tool a measuring head for Inclusion of a sensor provided is, the measuring slide and recording for that Tool to be measured can be positioned and locked relative to each other guided are.

Such measuring devices are known and are used for wear measurement and for quality control of Cutting tools used especially after regrinding. As for the function the tools authoritative Sizes have changed in practice the forehead clearance angle and the fore chip angle as well the flank clearance angle and (conditionally) the spiral angle have been proven. This Angles must be checked and reworked every time a cutting tool is reworked correct if necessary; Deviations of these angles from the given ones Values can shorten the service life of the tool and / or loss of quality of the machined workpieces pull yourself.

None is from the prior art measuring device for complete measurement of all angles of a rotary cutting tool, especially a face mill known. Usually is the dimensional accuracy the clearance and rake angle using a hair ruler based on the principle of Light gap control checked. Since the Accuracy of this measurement method to a large extent from testing personnel depends it turns out to be problematic in practice.

A device for measuring the rake angle of a milling cutter clamped in a grinding machine is known from the patent application DE 41 08 300 A1 known. A tool clamped in a spindle head of a machine tool is held immovably. A measuring head will. guided over columns and is mounted parallel to itself up and down lockable.

There are generic combination measuring devices for the Measurement of a wide range of parameters on cutting tools known, where the parameters, in particular the spiral angle, the relief grinding and the relief grinding stroke as well the division by means of a on a two-axis measuring slide arranged probe be measured.

With these measuring devices, the tool to be tested in one around the tool longitudinal axis rotatable holder clamped by moving the holder and Setting the measuring head by means of the measuring chute approached the measuring position, in the a probe touches down on the circumferential edge. By turning the tool in the Recording and possibly tracking the probe by means of of the measuring slide the spiral angle is then measured indirectly.

In the patent CH 566 540 a device for measuring rake angles and clearance angles for cutting tools is presented, but has no holder for the tool to be measured.

For complete measurement of all angles of the Cutting geometry of a cutting tool, however, the measuring devices must be converted, or must that Tool are clamped so that their use for the complete measurement all cutting edge angles are difficult to handle and therefore uneconomical proves. In addition, by retrofitting or lashings the vulnerability for measurement inaccuracies increased.

Object of the present invention is a measuring device for the To create cutting edge geometry of rotating cutting tools, that is easy to use and therefore economical to use and the measurement inaccuracies largely avoided.

The measuring device should in particular for the measurement the cutting of end mills be applicable.

The object is achieved in that the measuring head in the measuring directions for measuring the cutting edge angle, mainly the forehead free and Face rake angle and the flank clearance angle, is adjustable.

This way it is possible for everyone Measuring angles on a tool to be measured in one setup, without the measuring device must be changed. The handling of the measuring device is considerably simplified and measurement inaccuracies due to loop lashings or conversions are excluded.

A preferred embodiment the invention provides that the Adjustability of the measuring head in all measuring directions is achieved by the measuring slide holder by one The axis running at right angles to the tool axis is designed to be pivotable is that the Sensor once acts on the tool in the radial direction and after swiveling its direction of measurement is directed to the end plane of the tool.

It is also possible to put the measuring head in alone perform pivoting in the same way.

The basic position of the measuring head is assumed so that the measurement, when working with probes probing in the direction of its longitudinal axis, the measuring direction in the basic position is vertical and perpendicular to the longitudinal axis of the tool. In the basic position, the flan can easily kenfreiwinkel be determined. In the swivel position (90 °), the measuring direction runs parallel to the longitudinal axis of the tool, the measuring plane lies in the end face of the tool, so that the flank and front free angles can be measured with the same sensor.

wenn darin "x₁" und "x₂" die an den Meßpunkten 1 und 2 gemessenen Werte, d. h. die Abstände von der Meßbezugslinie und "1" der auf die Meßbezugslinie projizierte Abstand der Meßpunkte längs der Meßlinie ist.In a preferred embodiment of the invention, the angle measurement is carried out indirectly via a two-point measurement by means of a "vertical" sensor. By adjusting the measuring head, a sensor acting in the direction of its longitudinal axis is brought to a first measuring position on the cutting edge. The measured value recorded at this first measuring position can be defined as a measuring reference line, unless a fixed measuring reference line is specified by the geometry of the measuring head. From the first measuring point, the measuring head including the sensor is moved along the measuring line to a second measuring point, the distance between the two measuring points projected onto the measuring reference line being measured. The difference between the measured values, ie the distances of the measuring points from the measuring reference line in relation to the distance of the measuring points projected onto the measuring line, is a measure of the angle between the workpiece surface and the measuring reference line within the measuring point distance. The angle is calculated from the tangent relationship

if it contains "x ₁ " and "x ₂ " at the measuring points 1 and 2 measured values, ie the distances from the measuring reference line and "1" is the distance of the measuring points along the measuring line projected onto the measuring reference line.

Such a measurement is in principle with a continuous adjustment of the measuring head via z. B. micrometer screws possible, in which case the distance "1" can be read on the micrometer screw or by means of e.g. B. electrical Transducer must be saved in a computer.

The measurement is preferred embodiment of the invention carried out that on the measuring head Meßpunkteinstellung is provided by means of which the distance between two measuring points is constant and with which the measuring head in equidistant steps along the measuring line is moved.

In a simple way, a constant distance two measuring points achieved by in a in the measuring slide provided elongated hole an eccentric that rotates on a arranged on the measuring slide carrier Eccentric bolt is mounted. By turning the eccentric this arrangement of the measuring slide moved relative to and on the measuring slide carrier, the direction of movement by a provided side guide of the Measuring slide in Measuring slide carrier only linear runs. At the Measuring slide carrier arranged and on the measuring slide acting stops limit the displacement of the measuring slide so that in this way the measuring head the exact same distance between two measuring points for all measurements comply. For the measurement considered only the values measured by the sensors on the stops.

This version allows for use of dial gauges the direct use of an angle scale, the division of which from the through the stops predetermined intervals certainly. When using inductive or electromagnetic sensors, the attacks be provided with contactors, so that measured values only on the endpoints and, if necessary, transmitted to a computer become.

It is preferred to refer to the measurement reference line projected distance of the measuring points to 0.3 - 0.5 mm fixed, whereby finer and / or coarser divisions are possible.

A configuration considered to be particularly advantageous the invention is that an additional Sensor provided is whose direction of measurement perpendicular to both the longitudinal axis the tool to be measured as well as the measuring direction of the first sensor is. In the swivel position, this sensor can be used to measure the face rake angle be used. To measure the face rake angle with this sensor To carry out according to the principle of two-point measurement, the measuring points by means of the fine drive approached the column guide become.

Another advantageous embodiment the invention provides that a in the direction of the longitudinal axis of the tool acting setting device is provided so that about this Setting device the principle of two-point measurement also for measurement of the spiral angle can be applied to this measurement the first sensor in the basic position of the measuring head is used.

The setting device can both as a micrometer screw and as an eccentric adjustment of the measuring point distance be carried out in the manner shown above.

The invention is based on the following 1 - 7 explained. Show it:

1 a schematic diagram of the measuring device,

2 Principle sketch for measuring the flank clearance angle,

3 Principle sketch for measuring the face rake angle,

4 Principle sketch for measuring the forehead clearance angle,

5 Principle sketch for measuring the spiral angle,

6 a partial section through the measuring head of an embodiment of the invention and

7 a partial section along the line VII-VII in 6

1 shows a schematic diagram of a measuring device according to the invention.

On the machine bed 1 from z. B. Granite is the linear guide rail 2 for the linear guide 3 the recording 4 for the tool to be measured 5 established. At the recording 4 it is a clamping cone according to ISO 50. The linear guide 3 is non-rotatably designed in the specific application; on it can the recording 4 be prepositioned by hand in the measuring position, a superimposed, manually operated fine drive (not shown) serves for the exact positioning of the receptacle 4 , The recording 4 is also provided with a rotating device (not shown) so that the tool to be tested 5 rotated about its longitudinal axis and various measuring points can be set on the circumference.

To simplify the direction designation, the direction of movement of the recording 4 marked with "z".

Right-angled and at a distance from the axis of movement of the recording 4 is in the machine bed 1 the longitudinal guide column 6 for the measuring slide holder 7 arranged. In practice, the longitudinal guide of the measuring slide carrier 7 designed as a column guide with pre-tensioned, manually operated spindle adjustment (not shown). The direction of movement of the measuring slide holder 7 is denoted by "x".

The measuring slide holder 7 is mounted together with measuring slide 8 about the axis designated as "Q _S ". The tool 5 facing end of the measuring slide 8th is as a measuring head 9 trained and used to hold the sensor 10 , The sensor 10 acts in the basic position in the x direction (T _x ) at right angles to the longitudinal axis of the tool 5 ,

The measuring slide 8th is adjustable along the axis labeled Q on the measuring slide support 7 guided; the displacement of the measuring slide 8th and thus the measuring head 9 limit attacks 11 . 12 , The path of movement between the stops 11 . 12 is 0.4 mm and is characterized by the in 6 explained eccentric setting reached.

There is an adjustment device for measuring the spiral angle 13 intended for longitudinal displacement in the z direction, either as a micrometer screw or similarly as an eccentric adjustment 6 can be executed. The adjustment device 13 can both on the measuring head 9 directly as well as between measuring slide carriers 7 and the column guide. With the adjustment device 13 becomes the measuring head 9 moved by the measuring point distance in the z direction, so that for the measurement of the spiral angle a shift of the recording 4 is not necessary.

The sensor 10 is in the basic position of the measuring head 9 (Position shown with measuring direction of the sensor 10 in the vertical direction) for measuring the flank free angle and after swiveling the measuring slide support 7 by 90 ° about the Q _S axis for measuring the front free angle.

In addition to the sensor 10 (Tx) can the second sensor 14 be provided, the measuring direction in the pivot position perpendicular to the first sensor 10 and perpendicular to the longitudinal axis of the tool in the direction of the side of the cutting edge to be measured facing the chip 15 runs (direction Q). This sensor 14 is used to measure the face rake angle, with the measuring point distance for carrying out the two-point measurement by means of the fine drive of the measuring slide carrier 7 is set in the x direction. The position measurement of the measuring slide holder 7 is advantageously carried out on a glass scale.

The tool is used to carry out the measurement of the cutting edge geometry of a rotary cutting tool with the measuring device according to the invention 5 in the recording 4 clamped. By means of the linear guides of recording 4 and measuring slide holder 7 and the fine drives, not shown, the measuring position on the tool 5 approached. The measurement of the flank and forehead clearance angle as well as the front chip angle and the spiral angle is then carried out according to the in 2 - 5 measuring principles shown

In 2 is a cutting edge 15 shown on the flank of a face mill. The flank clearance angle is defined as the angle between the tangent to the circumferential circle defined by the radius of the cutting tip at the point of the cutting tip and the outer circumferential surface of the cutting edge 15 in the area of the cutting tip.

In the measuring device according to the invention, the flank clearance angle α _{F is determined} by means of the sensor 10 in the basic position of the measuring head 9 (Measuring direction in the direction of the x-axis). After positioning the probe 10 at the first measuring position (x,) by setting the holder 4 and the measuring slide carrier 7 the first measured value x _{1 is} recorded in its longitudinal guides. Then the measuring slide 8th in the measuring slide holder 7 by means of the 6 shown measuring point setting and the second measured value x ₂ recorded. The difference between the measured values and the distance 1 the measuring point gives the desired flank clearance angle via the tangent relationship.

For measuring the face rake angle after 3 becomes the measuring head 9 brought into the swivel position. The sensor 10 then acts in the direction of the z-axis and can in principle as before 2 described.

The forehead clearance angle is after the in 4 shown measuring principle with the probe 14 measured. This sensor 14 Since it is rarely used in practice, it can normally be swung out of the measuring range. The direction of action of the sensor 14 is in the swivel position of the measuring head 9 the direction T _Q , the measuring point distance is by means of the fine drive by moving the measuring head 9 set on the column guide. The angle is calculated according to the 2 explained principle.

The sensor is used to measure the spiral angle 10 in the basic position of the measuring head 9 used. The distance between the measuring points is set using a micrometer screw in the z direction or using a second screw on the measuring slide holder 7 arranged and acting in the z direction eccentric setting similar 6 , The measuring point setting can also be set via a setting 4 along the z axis via the fine drive there. The angle calculation is based on the 2 explained principle.

The evaluation and Conversion into angles with constant measuring point distance immediately in scale values e.g. a dial gauge be specified. The sensors can also equipped with signaling devices or be designed as electronic displacement sensors whose signal is calculated and displayed in an attached computer for the angle.

The 6 and 7 show partial sections through a device for measuring point adjustment in the Q direction. The measuring slide holder 7 is pivoted about the swivel axis (Q _S ) and in the measuring position by tightening the bolt 23 locked. The stops for the end positions of the pivoting movement are not shown. On the measuring slide carrier 7 is the measuring slide 8th guided longitudinally. On the tool to be measured 5 facing end of the measuring slide 8th is the sensor 10 , here a "vertical" dial gauge, arranged, the measuring foot 16 by a in the measuring slide carrier 7 arranged elongated hole 17 on the cutting edge to be measured 15 passed through. In the measuring slide holder 7 is the eccentric bolt 18 set on which the "conical" eccentric 19 is rotatably mounted. The eccentric 19 reaches into a "conical" slot 20 of the measuring slide 7 one and can with the control 21 be rotated. A rotation of the eccentric 19 moves the measuring slide 8th in the Q direction, the measuring head 9 including sensor 10 is thus moved by measuring length l from measuring point "a" to measuring point "b". The displacement of the measuring slide 7 is through the attacks 11 . 12 limited and therefore the same for all measurements. The measuring length l is preferably 0.4 mm.

7 shows a partial section of the representation 6 along the line VII-VII shown there. In this representation it can be seen that the measuring head 9 in a longitudinal groove 22 of the measuring slide holder 7 guided and fixed laterally.

The sketches shown represent an exemplary embodiment of the invention. Beyond this exemplary embodiment, further concretizations of the measuring devices according to the invention, which are not explained in more detail, are conceivable. In particular, it is to be regarded as an embodiment according to the invention if, because of practical circumstances, measurements of the rake and spiral angle are not necessary and for this reason both the second sensor 14 as well as the adjustment device 14 drop in the z direction.

 1

machine bed

2

Linear guide rail

 3

linear guide

4

admission

 5

Tool

6

Longitudinal guide column

 7

Meßschlittenträger

8th

measuring slide

 9

measuring head

10

probe

 11 12

attacks

 13

adjustment

 14

second probe

15

cutting edge

 16

measuring foot

17

Long hole

 18

eccentric

19

eccentric

 20

Long hole

21

operating element

 22

longitudinal groove

23

bolt

Claims (12)

Device for measuring the cutting angle on rotary cutting tools, consisting of a holder ( 4 ) for the tool to be measured ( 5 ), a measuring slide holder ( 7 ) on which a measuring slide ( 8th ) is guided in a longitudinally displaceable manner, on the tool ( 5 ) end facing a measuring head ( 9 ) with a sensor ( 10 ) is arranged, the measuring head ( 9 ) and the recording ( 4 ) for the tool ( 5 ) can be positioned and locked relative to each other, characterized in that the measuring head ( 9 ) for measuring the cutting edge angle of a rotating cutting tool, decisive for measuring the front and flank free angle, can be set in different measuring directions. Device according to claim 1, characterized in that the measuring slide carrier ( 7 ) is designed to be pivotable about an axis (Q _S ) perpendicular to the longitudinal tool axis into a plane parallel to the end plane. Device according to claim 1 or 2, characterized in that the measuring slide ( 8th ) perpendicular to the longitudinal axis of the tool to be measured ( 5 ) is guided displaceably and the displacement takes place in equidistant steps by means of a measuring point setting. Apparatus according to claim 3, characterized in that the measuring point setting by an in an elongated hole ( 20 ) of the measuring slide ( 8th ) intervene the eccentric ( 19 ) is formed, which is on a on the measuring slide carrier ( 7 ) arranged eccentric bolts ( 18 ) is rotatably mounted so that by rotating the eccentric ( 19 ) a displacement of the measuring head ( 9 ) takes place along the measuring line. Apparatus according to claim 4, characterized in that the displacement path of the measuring head ( 9 ) on the measuring slide ( 8th ) acting stops ( 11 . 12 ) is limited. Device according to one of claims 3 or 5, characterized in that that the Length of the equidistant Steps is 0.4 mm. Device according to one of claims 3 to 6, characterized in that the measuring sensor ( 10 ) only responds in the end positions (a, b) of the displacement path. Device according to claim 1, characterized in that a second sensor ( 14 ) is provided, the measuring direction of which extends in a plane which is in relation to the measuring direction of the first sensor ( 10 ) and is at right angles to the longitudinal tool axis. Device according to claim 8, characterized in that the second sensor ( 14 ) by means of a swiveling bracket ( 23 ) on the measuring slide holder ( 7 ) is arranged. Device according to claim 1, characterized in that a measuring head ( 9 ) adjusting device shifting in the direction of the tool longitudinal axis ( 13 ) is provided. Apparatus according to claim 10, characterized in that the adjusting device ( 13 ) is designed as a measuring point setting. Device according to claim 1, characterized in that the measuring head ( 9 ) is designed to be pivotable about an axis (QS) perpendicular to the longitudinal tool axis into a plane parallel to the end plane.