JPS59160708A - Device for detecting and controlling bending angle of bending machine - Google Patents

Abstract

PURPOSE:To improve working efficiency and bending accuracy by detecting a bending angle from the work under bending without contacting and controlling a ram driving mechanism according to the value thereof. CONSTITUTION:A blank 5 is bent between a die 2 installed on a die base 1a and a punch 4 attached to a ram 3. The end face of the blank 5 is detected by using an image sensor camera 8 from the light reflected from the end part. The detected image signal is converted to a binary signal by a threshold circuit 11 and is inputted to an image processor 12. The bending angle is calculated in accordance with the data inputted preliminarily to the processor. The operation of a ram 3 is controlled by the bending completion signal to be outputted when the bending angle attains a set angle.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bending angle detection control device for a folding machine that detects the bending angle of a blank machine that is folded by the folding machine.

Conventionally, in bending machines such as press brakes, the depth of the punch is determined each time depending on the material and thickness of the blank to be bent, the bending angle, and the amount of springback. For this reason, it is necessary to adjust the depth of the punch each time each of the above factors changes, which is cumbersome to operate, and even if the depth is adjusted to the specified value, the depth will change if the oil temperature rises during operation. Therefore, there was a problem that highly accurate bending could not be performed.

This invention was made to improve this problem, and involves optically detecting the bending angle of a blank material being bent by a bending machine, and controlling the bending machine using the obtained bending angle signal. By providing such a bending angle detection control device for a bending machine, highly accurate bending can be performed without requiring complicated depth adjustment.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.
In the figure, 1 is the bending machine main body, and on the die base 1a,
A die 2 having a V-shaped bending groove 2α is attached to the upper surface, and a punch 4 is provided above the die 2 by being attached to a ram 3 that can be moved up and down by a ram drive mechanism. The blank 5 can be bent at a predetermined angle between the die 2 and the die 2. Reference numeral 6 denotes a detection unit installed on one end side of the die base 1α, which includes a light source 7 that irradiates the end face of the blank 5 to be bent between the die 2 and the bunch 4 in the case δα, and An image sensor camera 8 that receives reflected light from the end face of the image sensor camera 8 is housed therein. As shown in FIG. 4, the image sensor camera 8 has a circular photodiode array 8af arranged on a circle with a radius R centering on a large number of photodiodes El)'COk, as shown in FIG.
A voltage proportional to the amount of light received is generated, and this voltage is input to the next threshold circuit 9. A threshold level setter 10 is connected to the threshold circuit 9, and the threshold level V is set in advance by the threshold level setter 10.
1 can now be set 29, and among the analog signals input from the image sensor camera 8, signals exceeding this threshold level are sent to the masking circuit 11.
It is now output to .

The masking circuit 11 removes all unnecessary parts of the input signal, converts it into a binary digital signal, and outputs it to the image processing device 12. The image processing device 12 has a built-in central processing unit, counts the input binary signal based on the information stored in the memory in advance, and calculates the entire bending angle of the blank 5. When the bending angle of the blank 5 reaches a preset angle, a bending completion signal is output to the input/output circuit 15 via the interface circuit 14, and the bending angle is displayed on the input/output circuit 15. A stop signal is output to the column drive mechanism 16, the lowering of the ram 3 is stopped, and the bending process of the blank 5 is completed.

Note that the seven photodiode array 8α of the image sensor camera 8 that detects the bending angle of the blank 5 includes photodiodes gb arranged at intervals of, for example, 10 μm on a central circle centered on Of.
The spectral characteristics range from near ultraviolet to near infrared, and the response characteristics range from 0.1 to 0.1.
1. It's as fast as 0m sec. In use, the blank 5 is detected by aligning the center O with the shoulder of the bending groove 2α of the die 2 as shown in FIG. When 8 h of photodiodes are arranged, 1
The resolution of each photodiode 8h is 907 m degrees, and by arranging a large number of photodiodes, highly accurate angle detection becomes possible.

Further, in the above embodiment, the photodiodes 8h are arranged in a circle, but a diode array 6α arranged in the radial direction may also be used.
If a photodiode array f3a in which seven photodiodes are arranged in a quadrant is used, the detection accuracy will be further improved.

As described in detail above, this invention detects the bending angle without contacting the workpiece during bending and controls the ram drive mechanism according to the detected value. No operations such as adjusting the depth are required, improving work efficiency and bending accuracy. In addition, since the bending angle of the workpiece is detected completely photoelectrically and the Sram drive is controlled based on the signal, the response is good, and the angle is detected with the bunch pressure unloaded, and the insufficient amount can be compensated for. If the machining is controlled, there is no need to input the springback te in advance according to the workpiece.

Moreover, because the image sensor camera uses a 7-otodiode array in which photodiodes are arranged in a circular (or radial) pattern, the amount of information is smaller than in conventional photodiodes arranged in a matrix. This makes it easier to perform bending and increases the processing speed, making it possible to perform bending control with higher precision.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, in which Fig. 1 is an overall diagram, Fig. 2 is a system diagram of the control system, Fig. 3 is an explanatory diagram showing the power-operated state, and Fig. 4 is a detailed diagram of the main parts. It is. 1cL is table, 2 is die, 3 is ram, 4 is punch,
5 is a workpiece, 8 is an image sensor camera, 8α is a diode array, 11 is a threshold circuit, and 12 is an image processing device. Applicant Komatsu Ltd. Representative Patent Attorney Masaaki Yonehara Patent Attorney Tadashi Hamamoto Figure 1

Claims (1)

[Claims] In a device in which a blank 5 is bent between a die 2 set on a die base lα and a punch 4 attached to a ram 3, the blank 5 is bent on the end side of the blank 5 by light reflected from the end. An image sensor camera 8 incorporating a photodiode array 8α in which photodiodes 8b are arranged in a circle (or radially) to detect the end face of the image sensor camera 8 is provided, and an image signal detected by the image sensor camera 8 is sent to a threshold circuit II. It is converted into a value signal and inputted to the image processing device 12, and the image processing device 1
In 2, the entire bending angle is calculated based on all the data input in advance, and when the bending angle reaches the set angle, a bending completion signal is output, and this bending completion signal causes the ram 3
This is a bending machine F4 degree detection control device that controls all the operations of the bending machine.