JPH0592352A - Inside measuring device for machine tool - Google Patents

Abstract

PURPOSE:To stably transmit the data of measurement from a differential transformer type measuring instrument provided on a turret without the occurrence of the problem of bad contact. CONSTITUTION:A turret 5 is provided with a differential transformer type measuring instrument 6, an amplifier 13 and a V/F converter 14. The light emitting element 16 and light receiving element 17 of a light emitting/light receiving signal transmitting device 15 are severally provided on the turret 5 and an irrotational member 18 on a fixed side. A V/F converted detection signal is noncontactingly transmitted as an optical signal between the light emitting element 16 on a turret side and the light receiving element 17 on a fixed side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-machine measuring device for a turret type machine tool such as a turret lathe.

[0002]

2. Description of the Related Art Conventionally, in a machine tool such as a turret lathe, there has been an in-machine measuring device for measuring a diameter of a work after machining, in which a rotating turret is provided with a differential transformer type measuring device.

As shown in FIG. 6, a differential transformer type measuring instrument 52 provided on a turret 51 has a rotary joint 53.
Each electric wire 56 is connected to a non-rotating side wire 57 such as a turret carriage via the, and signal processing is performed by the amplifier 54 and the A / D converter 55 to input measurement data to the NC device.

[0004]

However, since the rotary joint 53 is used for the transmission section of the measurement data,
External lead wire 5 may be caused by mist-like cutting oil or oil leakage.
There is a problem that contact failure occurs at the contact portion between 3a and the slip ring 53b.

Since the differential transformer type measuring instrument 52 has no contact at the detecting portion, it is advantageous in terms of life as compared with a touch sensor or the like, but it requires four electric wirings 56 and the number of wirings increases. When the rotary joint 53 is used as described above, poor contact is likely to occur.

An object of the present invention is to provide an in-machine measuring device for a machine tool capable of stably transmitting measured data from a differential transformer type measuring device provided on a turret without causing a problem of contact failure. Is.

[0007]

An on-machine measuring device for a machine tool according to the present invention is provided with a differential transformer type measuring device and an amplifier on a turret, and a light emitting element and a light receiving device of a light emitting / receiving signal transmitting device for transmitting the amplified signal. Elements are provided on the turret and the fixed member so as to face each other.

[0008]

According to this structure, the measurement signal detected by the differential transformer type measuring device of the turret is transmitted from the light emitting element of the turret to the light receiving element on the fixed side as an optical signal after amplification. Therefore, the measurement data is transmitted from the turret, which is a rotating body, to the fixed side wiring in a non-contact manner.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a schematic front view of the turret lathe. A main shaft 3 is provided on a bed 1 via a headstock 2, and a turret carriage 4 is installed laterally (in the X-axis direction) on a side of the headstock 2. The turret carriage 4 is mounted with a drum-shaped turret 5 so as to be capable of feeding back and forth (Z-axis direction) and rotating for indexing. At each tool station S, which is a peripheral surface of the turret 5, a turret 5 A tool (not shown) is attached.

A differential transformer type measuring instrument 6 for measuring the outer diameter of the machined workpiece W held by the spindle 3 is attached to one position of the tool station S of the turret 5.

The differential transformer type measuring instrument 6 measures the diameter of the work by sandwiching the work W between the contacts 7a, 7a provided on the two fingers 7,7. Link mechanism with built-in relative displacement of 7 (not shown)
Is converted into a linear movement of the core 8 in FIG. Core 8
Is arranged between the primary coil 9 and the two secondary coils 10 and 11, and the difference in the electromotive force of the two secondary coils 10 and 11 caused by the position of the core 8 becomes the displacement output. Of the four wirings 12, 12a and 12b are output signal lines, 12c and
12d is a power supply line.

As shown in FIG. 1, each wiring 12 of the differential transformer type measuring instrument 6 is connected to an amplifier 13 provided in the turret 5, and measurement data consisting of a voltage signal is sent to a V / F converter 14. It is converted into a frequency-modulated pulse signal via the light emitting element 16 of the light emitting / receiving signal transmitting device 15 to emit light. The light emission / reception signal transmission device 15 may transmit infrared light in addition to visible light.

In the light emitting / receiving signal transmitting device 15, the light emitting element 16 is provided on the turret 5 and the light receiving element 17 is provided on the fixed side member 18. The light signal of the light emitting element 16 is received by the light receiving element 17 and F / The V converter 19 restores the voltage signal, the A / D converter 20 converts it to a digital signal, and transmits it to the NC device. The fixed member 18 is a general term for non-rotating members such as the bed 1 and the turret carriage 4.

The power supply of the amplifier 13 provided in the turret 5 is
In this embodiment, the DC power source 21 on the fixed side is used. Ground the negative terminal of the DC power supply 21 and connect the positive terminal to the turret 5 with the rotary joint 22 of one contact.
It is connected to the DC / DC power converter 23. The smoothing capacitor C3 between the rotary joint 22 and the DC / DC power converter 23 is interposed, by interposing a capacitor C _1, C ₂ for smoothing between the DC / DC power converter 23 and the amplifier 13, the rotary joint 22 It is designed to absorb the voltage instability caused by the contacts.

FIG. 2 shows a schematic cross section of the turret 5. The turret 5 is attached to a hollow turret shaft 24 that rotates for indexing, and a non-rotating coolant pipe 25 passes through the center of the turret shaft 24. At the tip of the coolant pipe 25, the non-rotating member 2 forming a part of the fixed-side member 18
6 is fixed.

The turret 5 has an amplifier 13, V /
A measurement unit 27 incorporating the F converter 14 and the DC / DC power converter 23 is attached, and the light emitting element 16 is provided on the outer surface thereof. The light receiving element 17 is a non-rotating member 26.
Is provided apart from the rotation center of the turret 5, and the differential transformer type measuring instrument 6 of FIG.
The light emitting element 16 faces the light receiving element 17 at the indexing angle of. The power source rotary joint 22 is provided at the center of the non-rotating member 26, and the signal wiring of the light receiving element 17 and the power source wiring of the rotary joint 22 are combined into a single multi-core cord 28. The turret shaft 24 is pulled out to the rear.

According to this structure, the detection signal of the differential transformer type measuring instrument 6 of the turret 5 is transmitted as an optical signal from the light emitting element 16 to the light receiving element 17 of the fixed side member 18 after amplification and V / F conversion. It Since the signal is transmitted in a non-contact manner as described above, it is possible to stably transmit the measurement data without causing the problem of poor contact.

Although the rotary joint 22 having one contact is used for the power source of the amplifier 13, since it is for the power source, the instability of the contact can be absorbed by smoothing and the number of contacts is one. There is no problem in practical use.

FIG. 5 shows another embodiment. This example is shown in Figure 1.
A battery 29 is provided in the measurement unit 27 of the turret 5 as a power source of the amplifier 13. Further, the reed switch 31 for turning on / off the power source is provided on the turret 5 and the magnet 30 is provided on the non-rotating member 26 so that the battery 29 causes the amplifier 13 ( 3). Battery 2
A lithium battery, a nickel-cadmium rechargeable battery, or the like can be used as the battery 9.

In the case of this structure, since a rotary joint is not necessary at all, more stable signal transmission can be performed. Further, since the reed switch 31 is used to turn on only when necessary, the battery life can be prolonged.

Although the above embodiment has been described for the case of being applied to a lathe, the present invention can be applied to turret type machine tools in general.

[0022]

The on-machine measuring device for a machine tool according to the present invention is
The measurement signal of the differential transformer type measuring instrument provided in the turret,
After the amplification, the light-emitting element of the turret is transmitted as an optical signal to the light-receiving element on the fixed side. Therefore, measurement data can be transmitted from the turret, which is a rotating body, to the fixed-side wiring in a non-contact manner. Therefore, there is an effect that the measurement data can be stably transmitted without causing a problem of poor contact.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electrical configuration of an embodiment of the present invention.

FIG. 2 is a schematic horizontal sectional view of the turret.

FIG. 3 is also a schematic front view of the turret lathe.

FIG. 4 is an electric circuit diagram of the differential transformer type measuring instrument.

FIG. 5 is a schematic horizontal sectional view of a turret in another embodiment of the present invention.

FIG. 6 is a block diagram of a conventional example.

[Explanation of symbols]

5 ... Turret, 6 ... Differential transformer type measuring instrument, 12 ... Wiring, 13 ... Amplifier, 14 ... V / F converter, 15 ... Light emission /
Light receiving signal transmission device, 16 ... Light emitting element, 17 ... Light receiving element,
18 ... Fixed side member, 19 ... F / V converter, 21 ... DC power supply, 22 ... Rotary joint, 27 ... Measuring unit,
W ... work

Claims (1)

[Claims] 1. A differential transformer type measuring instrument and an amplifier are provided on a turret, and a light emitting element and a light receiving element of a light emitting / receiving signal transmitting device for transmitting the amplified signal are respectively opposed to the turret and the fixed side member. In-machine measuring device of machine tool provided.