JPH085040Y2 - Malfunction prevention device for automatic cutting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a malfunction prevention device for an automatic cutting device, and more particularly to a device suitable for preventing malfunction of a water jet cutting system. Is.

(Prior Art) As a malfunction prevention device of a conventional automatic cutting device, one applied to a water jet cutting system 1 is shown in FIG. A water jet nozzle body 4 is fixed to a robot wrist 1, and a water jet W (hereinafter, simply referred to as a nozzle) 5 at the tip of the body is jetted with a water jet W to be fixed on a jig 11. Cut off the body 12. In this device, the distance between the nozzle 5 and the workpiece 12, that is, the amount of deviation in the height direction is detected by the height direction deviation amount detection ring 6, and the signal is amplified by the height direction deviation amount detection sensor 3. Then, the data is output to the control unit that controls the robot wrist 1. In this way, the position in the height direction is controlled, and the operation is stopped when the deviation exceeds the allowable range. However, it is impossible to detect the deviation of the cutting line on the workpiece 12, that is, the lateral deviation, and it is impossible to prevent the cutting amount from becoming excessive.

As another malfunction prevention device for the conventional automatic cutting device, there is a laser processing device as disclosed in Japanese Utility Model Laid-Open No. 1-105086. This is to prevent a malfunction in an apparatus for cutting a maskant film using a laser beam in a chemical milling process. The distance between the workpiece and the processing head is measured, and the output of the laser beam is controlled in accordance with this distance to perform correction according to the distance in the height direction.

However, as described above, in the conventional apparatus, there is a problem that a trouble occurs in a program for moving the processing head, etc., and even if the trajectory of the cutting point is deviated, it cannot be detected, and the cutting amount becomes excessive. .

Further, in this device, a sensor for measuring the film thickness of the maskant film is provided around the machining head. However, when the machining head is provided at the tip of a 5-axis robot and moved to trim the contour surface, There is a problem that the orientation of the processing tool is uniquely determined, the distance between the processing head and the workpiece cannot be accurately measured, and the processing accuracy is reduced.

(Problems to be solved by the invention) As described above, the conventional device cannot accurately measure and control the distance between the machining head and the workpiece, and prevents the machining accuracy from being lowered due to excessive cutting. I couldn't.

The present invention has been made in view of the above circumstances, and an automatic cutting device capable of preventing an excessive depth of cut while maintaining a constant distance between a workpiece and a processing head and improving processing accuracy. It is an object of the present invention to provide a malfunction prevention device.

[Constitution of device]

(Means for Solving the Problem) The present invention is an apparatus for preventing malfunction of an automatic cutting device for cutting a non-ferrous workpiece by ejecting a fluid from a nozzle, and is provided on the surface of the workpiece. A template that has an outer shape that follows the cutting line, a ring that is slidable along the longitudinal direction of the nozzle around the center of the nozzle, and is attached to the ring. ,
A lateral deviation detection sensor that outputs a first signal when it approaches the template by a predetermined distance or more, and a height direction deviation that outputs a second signal when the deviation of the distance from the workpiece mounted on the ring exceeds a predetermined range. A sensor for quantity detection, a first signal,
Alternatively, it is characterized by comprising stop means for stopping the cutting operation of the automatic cutting device when at least one of the second signals is output.

(Operation) When the center of the nozzle, that is, the cutting point, shifts laterally from the cutting line and approaches the template, the lateral shift detection sensor detects this and outputs the first signal. Further, when the deviation of the distance between the nozzle and the workpiece exceeds a predetermined allowable range, the height direction deviation amount detection sensor outputs a second signal. The stopping means stops the cutting operation when at least one of the first and second signals is output. This not only keeps the distance in the height direction between the workpiece and the nozzle constant,
A situation in which the nozzle shifts in the lateral direction and causes excessive cutting is avoided, and processing accuracy is improved.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

This is a device intended to prevent malfunction of the water jet cutting system, and its structure is shown in FIG.

The difference from the conventional device shown in FIG. 6 is that
A template 14 having an outer shape following the cutting line is attached to the surface of the workpiece 12, and a lateral deviation detection sensor 7 is attached to the outer circumference of the height direction deviation amount detection ring 6. It is a point. The template 14 is made of metal, and the lateral deviation detection sensor 7 detects the proximity of the template 14. The other same components are given the same numbers and their explanations are omitted.

As shown in FIG. 2 showing a cross section taken along the line AA of FIG. 1, a plurality of the lateral deviation detecting sensors 7 are arranged around the height direction deviation detecting ring 6. Each lateral deviation detection sensor 7 is connected to a sensor amplifier 21 as shown in FIG. 3, and each sensor amplifier 21 controls the operation of the robot wrist 2 (FIG. 1) of the robot 23. Connected to the robot controller 22. The robot controller 22 has a function as a stopping means. Further, similar to the conventional device, when the deviation of the distance between the nozzle 5 and the work piece 12 exceeds a certain allowable range, the height direction deviation amount detection ring 6 detects and outputs a second signal. And stop the cutting operation.

The operation of this embodiment having such a configuration will be described with reference to FIGS. 4 and 5 in which the relative positional relationship between the lateral deviation detection sensor 7 and the template 14 during cutting is enlarged.

As shown in FIG. 4, when the template 14 is located outside the detection area A of the lateral deviation detection sensor 7, the tip of the nozzle 5 corresponding to the cutting point is outside the cutting line. . At this time, the first signal that detects the proximity of the lateral deviation detection sensor 7 to the template 14 is not output, and the robot controller 22 causes the robot controller 22 to
Let 23 continue the cutting work.

Lateral deviation occurs in the trajectory of the nozzle 5 during cutting, and the detection area A
When the template 14 enters within the range, the lateral deviation detection sensor 7 outputs a first signal, and the sensor amplifier 21 amplifies this signal and gives it to the robot controller 22.
As a result, the robot controller 22 determines that an emergency stop should be made and stops the operation of the robot wrist 2. In such a case, the wardget pump system also needs to be similarly stopped, and the injection of the ward jet W from the nozzle 5 is stopped in conjunction with the stoppage of the operation of the robot wrist 2.

As described above, according to the present embodiment, even if the program for operating the robot 23 is erroneous and malfunctions, the nozzle 5 does not come closer to the template 14 side than the cutting point, and excessive cutting is prevented. A plurality of lateral deviation detection sensors 7 are arranged on the outer periphery of the nozzle 5 with the center of the nozzle 5 corresponding to the cutting point as an axis. Therefore, it is possible to sense the outer shape even when the orientation of the processing tool is uniquely determined, as in the case where the operation of the nozzle 5 is controlled by using a 5-axis portal robot. Is.

In addition, in this embodiment, when the template 14 is installed on the workpiece 12, the rubber sheet 13 is attached to the surface of the workpiece 12, and the template 12 is attached to the rubber sheet 13. Therefore, even when cutting a workpiece 12 that has twists and has variations among individual components, like a composite component of an aircraft, the template 14 easily fits on the surface of the workpiece 13. It is possible to prevent overcutting with higher accuracy.

The above-described embodiments are merely examples and do not limit the present invention. For example, in this embodiment, the lateral deviation detection sensor has a high detection sensitivity and is made of metal so that it can be manufactured at low cost, but a material made of another material may be used.

[Effect of device]

As described above, according to the present invention, the lateral deviation detection sensor detects when the cutting point is laterally displaced from the cutting line, and the height is detected when the lateral deviation exceeds a predetermined range. Since the sensor for detecting the amount of misalignment detects and stops the cutting operation, not only the distance between the workpiece and the nozzle in the height direction is kept constant, but also the nozzle misaligns in the lateral direction and causes overcutting. This situation is avoided and the improvement of processing accuracy is achieved.

[Brief description of drawings]

FIG. 1 is a front view showing the appearance of a malfunction preventive device for an automatic cutting device according to an embodiment of the present invention applied to a water jet cutting system, and FIG. 2 is a vertical section taken along the line AA in FIG. Fig. 3 is a block diagram showing a path through which a signal is transmitted from the lateral deviation detection sensor to the robot in the same apparatus, and Fig. 4 is a lateral deviation detection sensor and a workpiece to be machined in the case of a normal cutting. 6 is a partially enlarged view showing the relative positional relationship with the body, and FIG. 5 is a partially enlarged view showing the relative positional relationship between the lateral deviation detection sensor and the workpiece in the case where lateral deviation occurs, FIG. Is a malfunction prevention device of the conventional automatic cutting device
It is a front view showing the appearance when applied to a cutting system. 1 ... Waterjet cutting system, 2
...... Robot wrist, 3 ...... Height direction deviation amount detection sensor, 4 ...... Water jet nozzle body, 5 ...... Water jet nozzle, 6 ...... Height direction deviation amount detection ring, 7 ...... Horizontal deviation Sensor for detection, 11 …… Jig, 12 ……
Work piece, 13 …… Rubber sheet, 14 …… Template,
21 …… Sensor amplifier, 22 …… Robot controller,
23 ... robot.

Claims (1)

[Scope of utility model registration request] 1. A device for preventing malfunction of an automatic cutting device for cutting a non-ferrous workpiece by jetting a fluid from a nozzle, the external shape being provided on the surface of the workpiece and following the cutting line. A template having a line, a ring provided on the outer periphery of the nozzle so as to be slidable along the longitudinal direction of the nozzle with the center of the nozzle as an axis, and a ring attached to the ring at a predetermined distance from the template. A lateral deviation detection sensor that outputs a first signal when the distances approach each other, and a height direction deviation amount detection that outputs a second signal when a distance deviation from the workpiece mounted on the ring exceeds a predetermined range. Sensor and stop means for stopping the cutting operation of the automatic cutting device when at least one of the first signal and the second signal is output. Malfunction prevention apparatus for the automatic cutting device comprising.