RU2564774C2 - Measuring method of axial runout of machine working element - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: invention relates to machine-building industry and can be used at testing of machines as to accuracy norms. For measurement of axial runout of a working element of a machine onto the end surface of the working element there installed is a support arm with a possibility of being turned relative to this surface through 180° in any position of the working element; with that, onto the other end of the support arm there installed is a measuring instrument that is adjusted relative to an end bar to a zero value at the initial measurement point. Then, measurements are made for initial position of the support arm relative to the working element of the machine and for its position after the arm is turned through 180°, and axial runout of the working element is determined as a maximum algebraic half-sum of deviations of readings of the measuring instrument from the zero value within one revolution of the working element.

EFFECT: application of the invention provides a possibility of improving accuracy and reducing test time, as well as simplifying an axial runout measurement technology.

3 dwg, 2 tbl

Description

The invention relates to the field of machine tools and can be used to test machines for accuracy.

A known method of measuring the axial runout of the working body of the machine, for example the machine spindle, by means of a mandrel with a ball fixed on its end, the center of which lies on the axis of the mandrel, a length measuring device and an intermediate plate with a clamp. In this method, a control mandrel with a ball is installed in the hole of the tested working body, the measuring device is installed on the stationary part of the machine coaxially with the tested working body of the machine so that its measuring tip touches the intermediate plate. The working body is brought into rotation at a speed that allows you to record the readings of the measuring device, while the runout of the working body is equal to the largest algebraic difference in the readings of the measuring device / GOST 22267-76. Metal-cutting machines. Schemes and methods for measuring geometric parameters.

The disadvantage of this method is that the hole made in the working body, in which the control mandrel is fixed, must have a minimum radial runout, so as not to affect the measurement results of the axial runout. In addition, it is technologically difficult to make a conical control mandrel, which should not have a radial runout relative to the surface of the ball, larger than the measured value of the axial runout, and in the case of a cylindrical hole, the working body must have an exact end surface on which the control mandrel is mounted. Moreover, in planetary spindles of coordinate grinding machines, it is difficult to make tapered or cylindrical holes accurate in shape and location for attaching control mandrels. Therefore, checking the axial runout of the planetary spindle of the coordinate grinding machine is carried out after its partial disassembly.

The closest in technical essence and adopted as a prototype is a method of measuring the axial runout of a tested working body, for example, a spindle of a machine having an end face, using two length measuring devices in which measuring devices are mounted on a fixed part of the machine so that their measuring tips touch the end surface of the tested working body at diametrically opposite points located at the same distance from the axis of rotation and perpendicular to the end howling surface. The working body is subsequently rotated by 45 ° and for each angular position, the readings of measuring instruments are recorded at points of contact with the end surface of the tested working body. The axial runout of the working body is equal to the largest difference in the arithmetic mean of the measuring instruments / GOST 22267-76. Metal-cutting machines. Schemes and methods for measuring geometric parameters.

The disadvantage of this method is the difficulty of ensuring the intersection of the axis of rotation of the working body and the line passing through the touch points of the measuring tips of devices for measuring lengths with the end surface of the working body, which reduces the accuracy of measuring axial runout. The use of two devices for measuring lengths, their adjustment and fulfilling the requirement of their location at the same distance from the axis of rotation for the vertical or horizontal arrangement of moving bodies is technologically difficult and involves the use of additional devices, which causes an increase in the complexity of the measurement. The disadvantage of this method is the need to ensure minimal face runout of the surface in contact with the measuring tips of two length measuring instruments, since axial runout is an integral part of face runout, therefore, it becomes difficult to estimate the proportion of axial runout in the measurement results.

The essence of the invention is to increase the accuracy of measurements of axial runout during rotation of the working body of the machine, simplifying the method of obtaining measurement results and their calculations, as well as eliminating the requirements for the shape and accuracy of the location of the end surface of the tested working body.

The technical result of the invention is to increase the accuracy of measurements of the axial runout of the working body of the machine during its rotation, reducing the complexity of the measurement process and simplifying the processing of the results.

The technical result is achieved by the fact that in the known method of measuring the axial runout of the working body of the machine by means of a measuring device and an end measure of length located on the stationary working surface of the machine table by successive rotations of the working body around its axis by a given angle of rotation, fixing the readings of the measuring device for each angular the position of the working body of the machine and processing the measurement results, the working body of the machine is additionally equipped with a cranked mandrel, one end of the cat swarm is fixed on the end portion of the inspected working machine body, and at its other end mounted measuring device, wherein the working body together with the mandrel and the bent measuring instrument has the ability to change the measurement plane relative to the stationary working surface of the machine table. The axial runout of the working body of the machine is defined as the largest, within one revolution of the working body, algebraic half-sum of the readings of the measuring device in the initial position and after turning the cranked mandrel 180 ° relative to the working body.

In the claimed method, in contrast to the analogue, a cranked mandrel is used to measure the axial runout of the working body of the machine and instead of two, only one measuring device is used. The cranked mandrel is mounted on the end surface of the working body and has the ability to rotate relative to the working body at any given angle.

Using the proposed method for measuring axial runout of the working body of the machine allows you to:

- to make measurements technically simple and to exclude the influence of the accuracy of the shape and location of the end surface on the measurement results of axial runout;

- eliminate the effect of radial runout of the working body of the machine on the axial runout;

- eliminate the need for precision holes, such as conical, for basing and installing a control mandrel;

- eliminate the need for manufacturing a high-precision control mandrel used in the measurement of axial runout;

- to exclude partial disassembly of the inspected working body for the measurement;

The essence of the proposed method for measuring axial runout of the working body of the machine is illustrated by drawings.

Figure 1 shows a diagram of the measurement of the axial runout of a planetary spindle located in a perpendicular position with respect to the surface of the machine table, which coincides with the longitudinal measurement plane.

Figure 2 shows the location of the planes (longitudinal, transverse, diagonal) of the measurement of the axial runout of the planetary spindle, which are at a given angle with respect to the working body of the machine.

Figure 3 shows a diagram of the measurement of the axial runout of a planetary spindle located in a non-perpendicular position, relative to the surface of the machine table, coinciding with the longitudinal measurement plane.

The following notations are used in the drawings: checked working body - 1, cranked mandrel - 2, measuring device - 3, end measure of length - 4, working surface of the machine table - 5, B - axial runout of the working body, N - non-perpendicularity of the working body to the table surface machine, L is the length of the measurement.

The tested working body 1 together with the cranked mandrel 2 and the measuring device 3 has the ability to rotate at any given angle around its axis of rotation and be installed in any measurement plane. The cranked mandrel 2, in turn, has the ability to rotate with the measuring device 3 relative to the tested working body 1 by 180 °. An end measure of length 4 is installed on the working surface of the table of the machine 5, having the ability to move along its surface, and is in contact with the tip of the measuring device 3 for measuring lengths, for example Mikator 0,5-IPM GOST 14712-79.

Measurements are carried out as follows: the tested working body 1, together with a cranked mandrel 2 fixed on it and a measuring device 3, is installed at one of the specified measurement points, for example, in the right position “P”. Moving the end measure of length 4 along the working surface of the table of the machine 5 until it contacts the tip of the measuring device 3, adjust the device to zero readings and record them in the measurement protocol in the column: position “P”. Then the tested working body 1 is installed in the left position "L" or 180 °, the end measure of length 4 is moved to this point and again brought into contact with the tip of the measuring device 3. The readings of the measuring device are recorded in the measurement protocol in the column: position "L" . After that, the inspected working body 1 is returned to the original right position "P". In this position, the cranked mandrel 2 is rotated 180 ° relative to the working tool 1 being checked and an end measure of length 4 is brought into contact with the tip of the measuring device 3 and the device is set to zero readings, the readings of the measuring device 3 are recorded in the protocol in the column: position “L” - left. Then, the tested working element 1, together with the cranked mandrel 2 and the measuring device 3 fixed on it, is rotated 180 ° and in this position again the end measure of length 4 is brought into contact with the tip of the measuring device 3 and the readings of the measuring device 3 are recorded in the protocol in the column: position "P". After that, the measurement results recorded in the protocol are processed.

The axial runout in a given measurement plane is equal to the algebraic half-sum of the readings of the measuring device 3 in the initial position and after a 180 ° rotation of the cranked mandrel 2 relative to the tested working body 1.

Below are examples illustrating the essence of the proposed method for measuring axial runout and the processing order of the measurement results.

Example 1

The axis of rotation of the tested working body is in a perpendicular position with respect to the surface of the machine table, which coincides with the longitudinal plane of measurement, that is, the non-perpendicularity H of the working body at the measurement length L to the surface of the machine table is 0 (H = 0 μm). The axial runout of the working body is directed, as shown in figure 1, and is 5 μm (B = 5 μm).

Table 1 shows the readings of the measuring device.

Table 1 The position of the cranked mandrel relative to the working body Meter reading The right position of the device "P" The left position of the device "L" Initial position 0 5 μm 5 μm = 0 μm + 5 μm After turning 180 ° 5 μm 5 μm = 0 μm + 5 μm 0

The axial runout for this case in the indicated plane is equal to the algebraic half-sum of the readings of the measuring device

$$B=\Delta \mathrm{about}\mathrm{from}.b=\frac{5+5}{2}=\frac{10}{2}=5\text{μm}$$

Example 2

The axis of rotation of the tested working body is in a non-perpendicular position relative to the surface of the machine table, coinciding with the longitudinal plane of measurement, the axial runout of the working body B is directed, as in Fig. 3, and is equal to 5 μm (B = 5 μm), non-perpendicularity of the working body N on the measurement length L to the surface of the machine table is 16 μm (H = 16 μm).

Table 2 shows the readings of the measuring device.

table 2 The position of the cranked mandrel relative to the working body Meter reading The right position of the device "P" The left position of the device "L" Initial position 0 -11 μm-11 μm = -16 μm + 5 μm After turning 180 ° 21 μm 21 μm = 16 μm + 5 μm 0

The axial runout for this case in the indicated plane is equal to the algebraic half-sum of the readings of the measuring device:

Thus, the proposed method for measuring the axial runout of the tested working body allows one to determine the axial runout as the algebraic half-sum of the readings of the measuring device in the initial position and after 180 ° rotation of the cranked mandrel in the given angular position of the tested working body or in the measurement plane corresponding to this position.

Changing the angular position of the working body or putting it in other measurement planes evenly located within the revolution of the checked working body, using the above method, find the maximum value of axial runout and take it for the measurement result.

The application of the proposed method for measuring the axial runout of the working body makes it possible to increase the accuracy of the check, simplifies the technology of measuring the axial runout, reduces the test time by using more accessible equipment, and also simplifies the processing of the results.

Claims (1)

A method for measuring the axial runout of a working body of a machine, including placing on a fixed working surface of a machine table an end measure of length, successive rotations of the working body of the machine around its axis by a predetermined angle, fixing the readings of the measuring device relative to the end measure of length for each angular position of the working body of the machine and processing the results measurements to determine the axial runout, characterized in that on the end part of the working body of the machine is fixed at one end of the cranked mandrel with the possibility of rotation relative to it by 180 ° in any position of the working body, while at the other end of the cranked mandrel the said measuring device is installed, which is set to zero at the initial measurement point, the measurements are made for the initial position of the cranked mandrel relative to the working body of the machine and for the position after turning the mandrel relative to the working body of the machine by 180 °, and the axial runout of the working body is determined as the largest within one revolution of the working Ghana algebraic half-sum of the meter readings deviations from zero.

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