JPH04256553A - Tracer control unit - Google Patents

Abstract

PURPOSE:To realize the tracer control function integrated in CNC without changing the basic structure of CNC. CONSTITUTION:A tracer control unit is composed as the CNC system 1 including the interface and multi-processor unit of plural linear scales. Now, the interface 31 of the linear scale is used with its connection with a displacement detector 9, as the interface for tracer control.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a profile control device.
In particular, it relates to a modularized profiling control device within a numerical control system (CNC).

0002

[Prior Art] Conventionally, when a stylus of a tracer head is brought into contact with a model surface, the tracer head decomposes the displacement received by the stylus into displacement amounts in each axial direction, converts it into a voltage signal, and sends it to a profiling control device. . The profiling control device converts this signal into a digital quantity and calculates the feed rate of each axis to form a command to the servo motor so that the displacement of the stylus is constant based on the amount of displacement of each axis. Based on this command, the servo motor rotates to relatively move the tracer head and the model, thereby performing tracing control along a predetermined locus on the model surface.

[0003] In such conventional profiling control devices, the profiling control function requires an interface such as an AD converter in order to convert the stylus voltage signal into a digital signal or convert the calculation result back into an analog command. It is. However, in recent years, a system has been developed that outputs the stylus signal digitally and also digitally gives commands to the servo motor, thereby increasing the speed and performance of the profiling control device. Additionally, along with this, the tracing function has come to be incorporated as a function of the NC device in a modular configuration inside the numerical control device. That is, the profiling function can be realized with a single NC device without having to connect the profiling control device and the NC device one by one, and the interface with the machine tool side can also be greatly simplified.

0004

However, despite the modularization of the tracing function and its integration with the CNC as described above, dedicated hardware is still required for the tracing control interface. That is, a dedicated interface board for tracing is required to input the displacement detection signal from the stylus, and the main CNC
In order to integrate with the PU and execute calculations at high speed, a multiprocessor unit (MPU) dedicated to profile control is required.

[0005] Therefore, when the system configuration of the CNC is updated, it is not possible to configure a profiling control system using the conventional profiling function module. In other words, a design change is also required for the hardware dedicated to the profiling control, resulting in an increase in the cost of the profiling control device.

[0006] The present invention has been made in view of the above-mentioned points, and it is possible to apply the tracing control function built into the CNC to the CNC.
It is an object of the present invention to provide a tracing control device that can be realized without changing the basic configuration of C.

[0007]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a tracing control device including a plurality of linear scale interfaces and a multiprocessor unit, in which a part of the plurality of linear scale interfaces is subjected to tracing control. A profiling control device is provided that is characterized in that it is used as an interface.

[0008]

[Operation] CN without changing the basic configuration of CNC.
A profiling controller can be constructed using the linear scale interface function that is part of the C hardware.

[0009]

Embodiments Hereinafter, embodiments of the present invention will be explained based on the drawings. FIG. 1 is a block diagram showing a first embodiment of a profile control device. The CNC system 1 includes a main CPU 2 and a servo interface unit 3 connected to the main CPU 2 via a bus line 4. The servo interface unit 3 includes ROM, RAM
It is composed of modules centered on an MPU (multiprocessor unit) that includes memory such as. This servo interface unit 3 further outputs command signals from the MPU, serves as an input/output interface for inputting feedback signals to the MPU, and normally controls position signals from resolvers, inductors, optical scales, etc. A linear scale interface 31 is provided. A command signal from the servo interface unit 3 is output to the servo motor 6 via the current amplifier circuit 5, and data on the rotation speed and position of the servo motor 6 is input to the servo interface unit 3 as a feedback signal from the position detector 61. ing.

Reference numeral 7 denotes table driving means driven by the servo motor 6, such as a ball screw. This table driving means 7 moves the model 8 in a predetermined direction by a servo motor 6 that rotates by a movement amount based on a command signal from the CNC system 1. The displacement detector 9 is, for example, a stylus, which contacts the surface of the model 8 and detects displacement according to its shape. The displacement amount of the displacement detector 9 is determined by converting an analog signal from a differential transformer in the tracer head 91 into a digital signal and outputting it for each axis component of x, y, and z.
Returned to 1. Here, the displacement detector 9 needs to output the amount of displacement as a digital signal suitable for the input function of the linear scale interface 31.

In the figure, only one signal line from the displacement detector 9 to the linear scale interface 31 is shown. When inputting the displacement amount for each axis to the CNC system 1 via the servo interface unit 3, it is necessary to add a linear scale interface 31. In that case, it is also possible to use a plurality of servo interface units 3 connected to the bus line 4.

FIG. 2 is a block diagram showing a second embodiment of the profile control device. Generally, the linear scale interface 31 is normally configured as a standardized module for the servo interface unit 3, and can be connected to a plurality of MPU buses as necessary. Therefore, in the second embodiment, in order to improve the accuracy of tracing control, a linear scale 71 is used to detect the actual movement amount and movement direction of the model 8 by the table driving means 7.
has been established. Then, the two-phase pulse signal from this linear scale 71 is inputted to the servo interface unit 3 via the linear scale interface 31, and the displacement amount from the displacement detector 9 is similarly received via another linear scale interface 32. I have to. Parts corresponding to the first embodiment in FIG. 1 are designated by the same reference numerals and will not be described here.

In the second embodiment, one MPU calculates the command signal to the servo motor 6 while also processing the amount of displacement from the stylus, and the main CPU 2 of the CNC system 1 performs tracing control. Therefore,
The processor is required to have sufficient processing power to maintain the speed and accuracy of profiling, but in any case, the profiling system can be constructed without changing the basic configuration of the CNC system 1.

[0014] In the above description, a tracing system is configured that inputs a displacement signal from a contact type displacement detector, but it is also possible to configure a tracing control device using non-contact distance detection means. . In addition, without simultaneous processing,
Even when configuring a digitizing device that creates digitizing data, the present invention can be applied to achieve similar effects.

[0015]

[Effects of the Invention] As explained above, in the present invention, CNC
Since the tracing system can be configured without changing the basic configuration of the system, it is possible to respond by simply changing the software without preparing a dedicated interface circuit board. Therefore, the cost of new development and design of hardware can be reduced, and the cost of the profiling control device can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of a profiling control device of the present invention.

FIG. 2 is a block diagram showing a second embodiment.

[Explanation of symbols]

1 CNC system 2 Main CPU 3 Servo interface unit 5 Current amplification circuit 6 Servo motor 8 Model 9 Displacement detector

Claims (2)

[Claims] 1. A profiling control device including a plurality of linear scale interfaces and a multiprocessor unit, characterized in that a part of the plurality of linear scale interfaces is used as a profiling control interface. 2. The apparatus according to claim 1, wherein model profile data input from a displacement detector via the linear scale is processed by the multiprocessor unit provided at an interface of the servo motor. Tracing control device.