JPH0156365B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for measuring the diameter of a workpiece machined with a large vertical lathe.

Conventionally, to measure the diameter of a workpiece machined with a large vertical lathe, a dedicated large micrometer was used, or blocks were placed opposite the outside diameter of the workpiece and the distance between the blocks was It was measured using a micrometer. In the former method, the large micrometer was heavy and difficult to operate, and there were problems with accuracy. In the latter method, it was difficult to place the block accurately in contact with the workpiece, and it was also difficult to connect the inside micrometer accurately. In addition to these methods, there is also a method in which the table on which the workpiece is placed is rotated, a roller with a known diameter is pressed against the measurement surface of the workpiece, and the diameter of the workpiece is calculated from the number of rotations of the roller. However, since there is a slip in the number of rotations of the roller that contacts the workpiece, accuracy decreases. Furthermore, when the roller is pressed, the part of the workpiece becomes glossy, which is objectionable.

The present invention has been made from this point of view, and its object is to provide an apparatus for accurately and efficiently measuring the diameter of a workpiece in a large vertical lathe.

The present invention will be explained below with reference to figures showing one embodiment. Figure 1 is a schematic side view of a large vertical lathe.
Above the bed 11 is a table 13 rotated by a drive mechanism 12, on which a workpiece 14 is placed. Columns 15 stand on both the left and right sides of the bed 11, and a horizontal digit 16 that moves up and down is attached to the column 15. A turret 17 that slides left and right is attached to the horizontal digit 16. A tool (not shown) is fixed to the tip of the ram 17A. In order to measure the diameter after cutting, the workpiece 14 is equipped with an inertial accelerometer (hereinafter referred to as an accelerometer) that measures the tangential acceleration on the measurement surface of the workpiece 14, and a rotational angular velocity meter (hereinafter referred to as an accelerometer) that measures the rotational angular velocity. Instruments 21 and 22, which are combined with a speedometer (hereinafter referred to as a speedometer), are attached. These meters 21 and 22 are connected to a calculation display mechanism 23 attached to the horizontal digit 16 or the like.

Next, details of the arithmetic and display mechanism 23 described above will be explained with reference to FIG. 2, together with its operation. When the cutting of the workpiece 14 is finished, the table 13 stops rotating, so the accelerometer 21 and the speedometer 22 are connected to the workpiece 14.
Attach it to the measurement surface. When the start signal generator 31 is activated here, the reset signal of the generator 31 is transmitted to the speed memory 33 of the integrator A32 and the integrator B34.
The displacement memory 35 of the integrator C36, the displacement memory 37 of the integrator C36, and the display section 43 are reset. Next, the integration start signal from the start signal generator 31 activates the clock pulse generator 38, so that the integrator 3
2, 34 and 36 start integral calculations.

Next, when the table 13 is started, the workpiece 14
The accelerometer 21 and speedometer 22 attached to the sensor transmit the tangential acceleration γθ and the angular velocity θ of the sensitivity center attached to the sensor. The tangential acceleration γθ¨ is converted into a digital signal by the A/D converter 39 and sent to the integrator A32, where it is integrated every moment and the tangential velocity γθ is input to the speed memory 33, and the output of the speed memory 33 is sent to the integrator A32. B34 receives and integrates the displacement memory 35.
The circumferential displacement γθ is input to the . On the other hand, the angular velocity θ is converted into a digital signal by the A/D converter 40 and sent to the integrator C36, where it is integrated every moment and the angle θ is input to the displacement memory 37.

The circumferential displacement γθ in the displacement memory 35 and the angle θ in the displacement memory 37 are both held and sent to the calculator 41, where γθ/θ+2 is calculated and the diameter is 2γ.
become. Next, the sensitivity center position of the accelerometer 21 with respect to the workpiece 14 is corrected by the corrector 42 and then displayed on the display section 43. It is preferable to issue the hold signal at the timing of one rotation in order to offset the rotational fluctuation of the table 13.

In FIG. 1, the diameter of the outer circumference is measured by attaching the accelerometer 21 and the speedometer 22 to the outer circumference of the workpiece 14, but if the accelerometer 21 and the speedometer 22 are attached to the inner circumference of the workpiece 14, The inner circumference can be measured.

As described above, the workpiece measuring device for a large vertical lathe according to the present invention includes a table rotatably supported on the bed, and an inertial acceleration sensor attached to the measurement surface of the workpiece placed on the table. a pair of A/D converters that convert the analog signals of the inertial accelerometer and rotational angular velocity meter into digital signals, and a pair of A/D converters that convert the analog signals of the inertial accelerometer and rotational angular velocity meter into digital signals, and convert the accelerometer signal of the A/D converter on one side into velocity and displacement. two integrators connected in series for conversion, and an integrator for converting the angular velocity signal of the A/D converter on the other side into an angle;
A calculator for dividing the displacement amount integrated by one integrator by the angle integrated by another integrator, and a calculator for correcting the sensitivity center position of the inertial accelerometer with respect to the mounting surface to the workpiece. It consists of a corrector that receives the connection, and a display section that displays the output of the corrector.

Therefore, according to the measuring device of the present invention, there is no need to use a large and heavy micrometer or inside micrometer, and the workpiece is simply rotated after attaching an accelerometer and an angular velocity meter to the measurement surface of the workpiece. The present invention has the effect of making it possible to perform highly accurate measurements because the operation is extremely easy and there is little room for error.

[Brief explanation of drawings]

Each figure shows an embodiment of the present invention, and FIG. 1 is a side view, and FIG. 2 is a mechanical diagram of the main part. 11... bed, 13... table, 14...
Workpiece, 21... Inertial accelerometer, 22... Inertial angular velocity meter, 32, 34, 36... Integrator, 39,
40...A/D converter, 41...calculator, 42...
...corrector, 43...display section.

Claims (1)

[Claims] 1 a table rotatably supported on the bed;
an inertial accelerometer and a rotational angular velocity meter attached to the measurement surface of the workpiece placed on the table;
A pair of A/D converters that convert analog signals of the inertial accelerometer and rotational angular velocity meter into digital signals, and a pair of A/D converters connected in series to convert the acceleration signal of the A/D converter on one side into velocity and displacement. an integrator for converting the angular velocity signal of the A/D converter on the other side into an angle;
A calculator that divides the amount of displacement integrated by one integrator by the angle integrated by another integrator, and corrects the sensitivity center position of the inertial accelerometer with respect to the mounting surface to the workpiece. A workpiece diameter measuring device for a large vertical lathe, comprising a corrector that receives the output of the calculator and a display section that displays the output of the corrector.