JPS60177847A - Tool breakage detecting apparatus - Google Patents

Abstract

PURPOSE:To detect the breakage of the cutting edge of a tool in high-speed revolution for each cutting edge at early time by installing a means for detecting the existence of the breakage of the cutting edge during grinding and during the time in which the breakage is little, onto a tool for milling a traveling metal plate. CONSTITUTION:The captioned tool breakage detecting apparatus detects the existence of the breakage of the cutting edge 3 of a rotary grinding tool in which the cutting edge 3 is fixed onto the blade base 4 installed onto the outer edge of a tool body 2 which revolves at a high speed. Said tool breakage detecting apparatus is equipped with a means which irradiates the detection light onto the blade base 4 part only and the parts of the blade base 4 and the cutting edge 3 from the reflection type light- source switches 7 and 8 and receives the reflected light through optical fibers 5 and 6 and a means which receives the detection signal (a) for the reflection light supplied from the blade base 4 and outputs a sampling instruction signal (c). Further, the means which receives the signal (c) and receives the detection signal (d) for the reflected light supplied by the blade base 4 and the cutting edge 3 and outputs a blade breakage signal (g), according to the fact that the sampling instruction signal (c) is input or not within a prescribed time after the input of the signal (d) is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting chipping of an attached cutting edge.

A tool used in a machine tool or the like that continuously mills the end face of a moving metal plate is fixed to a tool body 2 and a blade rest 4 provided on the outer periphery of the tool body, as shown in FIG. It consists of a blade 3. In such a tool, it is important to detect the presence or absence of chipping of the blade 3 during cutting so that the chipping can be dealt with while the chipping is still minor.

The present invention is a tool damage detection device made in view of these circumstances. Hereinafter, embodiments of the present invention will be described based on the drawings. FIG. 1 is a functional book diagram showing the overall configuration, and FIG. 2 is a timing diagram. When the metal plate 1 is fed by a metal plate feeding device P into a tool body 2 that rotates at high speed and has a blade 3 and a blade stand 4 that supports the blade attached to its periphery, the end face of the metal plate 1 is cut. Chips produced by cutting are removed by a chip removal brush 9. After the chips attached to the blade 3 and the blade rest 4 attached to the tool body 2 are removed by a chip removing brush 9, the blade 3 is irradiated with detection light by a reflective photoelectric switch 8 and an optical fiber 6. , blade 3
If the blade is missing, the reflective photoelectric switch 8 does not output a signal because the amount of reflected light that returns to the reflective photoelectric switch 8 through the optical fiber 6 is small due to diffused reflection from the surface. If the blade base is not chipped, the amount of reflected light is large, so the reflective photoelectric switch 8 outputs a signal. The blade base 4 is irradiated with detection light by the reflective photoelectric switch 7 and the optical fiber 5, but since it does not come into direct contact with the metal plate 1, the irradiated surface is not roughened and the reflective photoelectric light passes through the optical fiber 5. The amount of reflected light returning to the switch 7 is large, so the reflective photoelectric switch 7 outputs a signal. Tool body 2
is rotating, so the reflective photoelectric switch 8 is activated when the blade 3 is not chipped and when the blade S is chipped on the back of the blade S, the part R other than the blade 2 and the blade rest 4 is rotated. No signal is output when the detection light is irradiated. The reflective photoelectric switch 7 is the blade base 4
A signal is output when the detection light is irradiated to the blade 4, and no signal is output when the detection light is irradiated to a portion R other than the blade base 4.

The output signal of the reflective photoelectric switch 7 is used as a signal to know that the blade 3 and the blade base 4 have entered the detection light irradiation area of the reflective photoelectric switch 8.

The blade chipping determination logic circuit φ is composed of a signal recognition circuit I, a sampling timing circuit J, a signal recognition circuit, a signal storage circuit, a signal sampling circuit M, and a delay circuit N.

The signal a output from the reflective photoelectric switch 7 is noise-removed by a photocoupler at the entrance of the signal recognition circuit I, and is then processed within the signal recognition circuit I for a signal recognition time of 1. It is checked whether the signal is input continuously during the period. If the signal has been input continuously for 13 hours, it is determined to be a knife base signal, and 1. After the time, the signal recognition circuit I outputs the cutting board signal. If the signal is not input continuously for 11 hours, it is determined to be an erroneous signal due to noise or chips, and is removed in the signal recognition circuit I, and the blade rest signal is not output. The cutting edge signal output from the signal recognition circuit I is input to a sampling timing circuit J. In order to sample the cutting edge signal input to the sampling timing circuit J and the force signal e at an appropriate time, the rising edge signal of the cutting edge signal is delayed by 12 hours, and then the rising sampling command signal C is generated.
It is output from the sampling timing circuit J as .

The signal d output from the reflective photoelectric switch 8 is a signal that is continuously input into the signal recognition circuit for a signal recognition time t4 after noise is removed by a photocoupler at the entrance to the signal recognition circuit. can be investigated. If the signal has been continuously input for 14 hours, it is determined to be a force signal, and the signal recognition circuit K detects the rear blade signal e at t4 hours after the signal d starts inputting.
Output from. If the signal is not input continuously for 14 hours, it is determined to be an erroneous signal due to noise chips, and is internally removed by the signal recognition circuit, so that the force signal e is not output. Signal recognition circuit K
The force signal e outputted from is input to the signal storage circuit. The force signal e input to the signal storage circuit is held within the signal storage circuit until a memory clear signal is input.

The force signal e held in the signal storage circuit is output as sampled data r.

Sampled data f output from the signal storage circuit
is input to the signal sampling circuit M. The sampled data f and the sampling command signal C are input to the signal sampling circuit M.
is delayed from the sampled data f, which is adjusted by the sampling timing circuit 51c. In the signal sampling circuit M, the sampled data f is sampled according to the command of the sampling command signal C, and as a result, when the sampling command signal C is input, if the force signal e is stored as the sampled data f, the blade 3 It is determined that the blade is not chipped, and the signal sampling circuit M does not output the signal g when the blade is chipped, as shown in FIG. 2(I).

If the force signal e is not stored as the sampled data f, it is determined that the blade 3 is chipped, and as shown in FIG.
continues to be output until the next sampling command signal C is input.

'The sampling command signal C output from the sampling timing circuit J is input to the signal sampling circuit M and the delay circuit N, but the sampling command signal C input to the delay circuit is processed by the signal sampling circuit MvC to the sampled data is delayed by the delay circuit N by the time until sampling is completed by the sampling command signal C, and then outputted from the delay circuit N as a memory clear signal. The memory clear signal output from the delay circuit N is input to the signal storage circuit.

The signal storage circuit clears the stored data when a memory clear signal is input. As a result, the sampled data f output from the signal storage circuit is also reset.

The timer for setting [1, t2, and t4 in the figure is a digital timer whose time width can be adjusted depending on the rotational speed of the tool body 2 and the dimensions of the blade 3 and the blade base 4. By adjusting this timer, it can be applied to a wide variety of edge mirrors.

As described in detail above, according to the present invention, chipped edges of a tool rotating at high speed can be detected for each blade even in a harsh environment with a lot of noise. As a result, machine tool operation can be stopped when the blade is only slightly damaged, greatly reducing the amount of work and time required to change the blade. In addition, since chipping can be detected for each blade, even if chipping is detected on several blades, it is possible to change the blade after grinding the metal plate while monitoring the state of the chipping. be.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing an embodiment according to the present invention, and FIG. 2 is a timing diagram. 3...Blade, 4...Blade stand, 5.6...Optical fiber, 7.8...Reflective photoelectric switch, ■, K...Signal recognition circuit, J...Sampling timer circuit, L
...signal storage circuit, M...signal sampling circuit,
N...Delay circuit diagram 1

Claims (1)

[Claims] A device for detecting the presence or absence of damage to the cutting blade of a rotary cutting tool, which has a cutting blade fixed to a blade rest provided on the outer periphery of the tool body, and includes a part only for the blade rest and a part for the blade rest and the cutting blade. means for respectively irradiating detection light with detection light and receiving the reflected light; means for inputting a signal detected by detecting the reflected light only from the blade base and outputting a sampling command signal; and means for inputting the sampling command signal and It is characterized by a trap and means for inputting a signal that detects reflected light from the blade base and cutting edge portion, and outputting a blade missing signal depending on whether a sampling command signal is input within a predetermined time after inputting the signal. Tool damage detection device.