JPH02232148A - Chip supervisory device for cutting machine - Google Patents

Abstract

PURPOSE:To supervise an adhering state by an unmanned manner by judging adhesion of chips to a cutter through picture processing of a camera image signal and controlling the next cutting action in accordance with a decision result. CONSTITUTION:A workpiece 4 is cut by a tool 2 taken a picture by a camera 5, consisting of a solid camera element, and decided for whether or not a cutting chip adheres by a picture processing circuit 6. By a result of this decision, when the cutting chip is decided present, the next cutting action is stopped by a control circuit 7. Accordingly, at the time of the next cutting, its action can be automatically controlled without causing damage in the workpiece by the cutting chip.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a chip monitoring device for a cutting machine such as a planing cutter, which monitors chips adhering to a cutting tool K.

[Conventional technology]

FIG. 5 is a front view showing a conventional cutting machine such as a planing machine. In the figure, 1 is a cutting machine, 2 is a pair of cutting tools that are vertically movable in the cutting machine 1K, and 3 is a cutting machine. 1 is a movably provided bed, and 4 is a workpiece placed on the bed 3.

Next, the operation will be explained. First, with the ped 3 moved to a position where the cutting tool 2 does not contact the workpiece 4,
The cutting tool 2 is lowered according to the cutting amount K. Next, when the bed 3 is moved toward the cutting tool 2, the workpiece 4 is moved toward the cutting tool 2.
By making contact with the cutting tool 2 and continuing to move the bed 3, the surface of the workpiece 40 is cut to a predetermined depth by the cutting tool 2. When a cutting stroke of a predetermined length is completed,
As the cutting tool 2 is lifted, the bed 3 enters the return stroke, moves in the opposite direction, and returns to its original position. Next, the cutting tool 2 is lowered again and positioned, and then the cutting stroke K is entered again and cutting is performed.

[Problem to be solved by the invention]

Conventional cutting machines are configured as described above, so when the chips adhere to or become entangled with the cutting tool during the cutting stroke, when the chips are removed from the cutting stroke and the next cutting stroke is started, the above-mentioned cutting The powder may damage the machined surface of the workpiece, so it is necessary for the operator to constantly monitor the cutting tool and remove the chips, and the operator cannot leave the cutting machine during machining. The problem has been solved.

This invention was made in order to solve the above-mentioned problems, and provides a chip monitoring device for cutting machines that can automatically monitor the adhesion of chips and can also stop the cutting machine in the case of adhesion of chips. The purpose is to obtain.

[Means to solve the problem]

A chip monitoring device for a cutting machine according to the present invention has a camera that detects chips adhering to a cutting tool, and based on the video signal, an image processing circuit determines the adhesion of chips, and based on the determination result. Data indicating whether or not to proceed to a cutting stroke is output to a control circuit, and the control circuit controls the next cutting operation of the cutting machine.

[Function] In the cutting machine chip monitoring device according to the present invention, when the image processing circuit determines that chips are attached, the control circuit
The next cutting operation is stopped.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, the same parts as in FIG. 5 are given the same reference numerals, and their explanation will be omitted. 5 is a camera composed of a solid-state image sensor for detecting chips adhering to the cutting tool 2; 6 is an image processing circuit that processes the video signal obtained from the camera 5; and 7 is chip adhesion determination data from the image processing circuit 6. This is a control circuit that receives the information and controls the cutting machine 1 accordingly.

Next, the operation will be explained. In FIG. 2, the cutting stroke indicates a period during which the bed 3 is moving in the cutting direction in order for the cutting tool 2 to cut the object 4 to be cut. The return stroke indicates the period during which the bed 3 moves in the opposite direction after the end of the cutting stroke. The knife lift is a period for lifting the cutting tool 2 and dodging the workpiece 4 immediately before entering the return stroke. The lowering of the cutting tool is a period in which the cutting tool 2 is lowered by the cutting amount immediately before entering the cutting stroke. Chip detection is performed by measuring the stop time of the bed 3 (the time to change direction from the return stroke to the cutting stroke) from the time from when the bite 2 is set to the cutting position until the bite 2 contacts the workpiece 4. This must be done during the subtracted period. When the image processing circuit 6 receives the data that the cutting tool 2 is in the cutting position from the control circuit γ, the image processing circuit 6 changes the video signal from the camera 3 to 0.
．． Processing is performed within 5 seconds, and data indicating a determination result as to whether or not chips were attached to the cutting tool 2 during the previous cutting stroke is transmitted to the control circuit 7. If the determination result is that chips are attached, the control circuit 7 stops the cutting operation of the cutting machine 10 and generates an alarm.

Next, an image processing method in the image processing circuit 6 will be explained. First, as shown in FIG. 3, a difference image is obtained based on the difference between a normal reference image with no chips attached and an abnormal image obtained from the camera 5 with chips 8 attached. In this difference image, only the chips 8 appear as shown.

Next, as shown in FIG. 4, a density distribution histogram for the entire difference image is created. The example in Figure 4 is 256
The case of gradation is shown, and there appears a peak that concentrates at zero with the density of T8 as the boundary, and a peak that concentrates at the density T of chip 8. If no chips 8 are attached to the cutting tool 2, the image from the camera 5 will be a normal image, so the density distribution histogram of the difference image will be concentrated only at zero.

Next, each pixel data constituting the above-mentioned differential image is converted into the above-mentioned Ts
After binarizing using the o value as a threshold value, the above threshold value Ts
Count the number of pixels that exceed . If this count value exceeds a predetermined set value, it is determined whether chips are attached.

In addition, since the back light for the bite 2 changes during the day, a detection error by the camera 5 occurs, so a normal image taken one stroke before is used as a reference image to obtain a difference image from the image obtained by the camera 5. By doing so, the above error can be reduced.

〔Effect of the invention〕

As described above, according to the present invention, the adhesion of chips is determined by image processing the video signal from the camera that photographs the cutting tool, and the next cutting operation is controlled according to the determination result. With this configuration, it is possible to unattended monitoring of the adhesion of chips, and there is an effect that damage to the cut object due to chips is eliminated.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a chip monitoring device for a cutting machine according to an embodiment K of the present invention, FIG. 2 is a timing chart of chip monitoring operation, and FIG. 3 is a diagram for explaining image processing of the device. FIG. 4 is a front view of the image, FIG. 4 is a density distribution histogram diagram for explaining image processing of the apparatus, and FIG. 5 is a front view of a conventional cutting machine. 1 is a cutting machine, 2 is a cutting tool, 4 is a workpiece to be cut, 5 is a camera, 6 is an image processing circuit, and 7 is a control circuit. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] a camera that photographs a cutting tool that cuts a workpiece after the cutting operation is completed; an image processing circuit that processes a video signal obtained from the camera to determine whether chips have adhered to the tool; and the image processing circuit that processes the video signal obtained from the camera. A chip monitoring device for a cutting machine, comprising: a control circuit that controls the next cutting operation by the cutting tool according to a determination result of the circuit.