Abstract: In a machine tool such as a machining center or the like having an automatic tool changing apparatus, the tool holders adapted to respectively hold the tools provided for the automatic tool change are equipped with transmitters for transmitting signals indicative of tool data including the tool discrimination data of the tools. The receiver which receives the transmitted signals from the transmitters is attached to the machine tool. When a transmitter approaches the receiver, the transmitted data is received by the receiver. The kind and other data concerning the tool stored in the tool holder to which a transmitter is attached can be discriminated by the control unit of the machine tool on the basis of the received data.

Abstract: A microwave proximity detector includes a microwave oscillator circuit having a dielectric resonator, or having a micro strip line as an inductor thereof so as to sense a change in an oscillation frequency or output from the oscillator circuit caused by a variation in an impedance of a circuit including the dielectric resonator, or of the micro strip line, due to a loss which takes place in a leakage magnetic field from the micro strip line when an object approaches the leakage magnetic field, thereby detecting an object in the neighborhood of the switch.

Abstract: The tool monitor according to this invention comprises an acoustic emissions (AE) sensor to be mounted in the neighborhood of and without contact with a machine tool and a tool damage detection means adapted to detect any damage to a tool of the machine tool according to a level of an output AE signal within a predetermined frequency band generated from the AE sensor at the time of occurrence of damage. Since this AE sensor is not in contact with the machine tool spindle, work table or work piece, it is easy to set the sensitivity of the AE sensor and variations in the AE sensor output signal level are minimized. The AE sensor is also effectively protected against flying chips, and noise due to contact with the chips is reduced, thereby minimizing the possibility of erroneous operation.

Abstract: An article identifying system comprises an ID device attached to an article to be identified and a write/read control apparatus to write and read data into and from the ID device. The control apparatus has an oscillator. The ID device has a resonance circuit. Data transmission is performed by the electromagnetic coupling of the oscillator and resonance circuit. The FSK modulation/demodulation are used in this data transmission. Preferably data is encoded by bi-phase code, f/2f code, bipolar code, or dicode code. An electric power can be also supplied from the control apparatus to the ID device by the continuous oscillation of the oscillator.

Abstract: A reflection-type photoelectric switching apparatus for providing an electric switching signal indicating existance information of an object to be detected thereby comprising a light projecting device for projecting a beam of light to the object, a light receiving photoelectric device arranged in side-by-side relation with the light projecting device for receiving a reflected light from the object, an optical axis adjusting means which is controllable from outside of housing of the apparatus for adjusting the optical axes of the light projecting and receiving devices, and optical members which allow both the light beam from the projecting device and the light beam to be incident on the receiving device to pass within a predetermined light path so that the two light beams will be crossed in a desired detection field, the distance from the apparatus to the desired detection field being continuously variable by the optical axis adjusting means.