Abstract: The invention relates to a device and method for analysis of a tool 50 e.g. used on a machine tool. A tool detector 5 includes a light emitter 12 and a light receiver 34. Tool 50 when progressed into a beam 20 of light emitted from the emitter 12 will cause a signal from the receiver to change. Circuitry 32 includes a digital signal processor which processes the signal from the receiver and produces an output only if the signal conforms to a predetermined condition. Preferably this predetermined condition could be e.g. a characteristic shape of the signal from the receiver, a change in a value derived from a succession of such signals or a change in the minimum or maximum values of a succession of signals from the receiver.

Abstract: A device and method for detecting the presence or absence of an object which has repetitive motion are disclosed comprising, a receiver for receiving a signal from the object, and circuitry for determining the presence or absence of the object to be detected, wherein the circuitry records the signal from the receiver as a pattern of data during at least part of the repetitive motion of the object, compares the data with a previously recorded data pattern and, produces an output signal based on the comparison. The signal may be received during discrete time intervals, and may be light which can be transmitted with varying intensity. The circuitry may determine the value of signal received at a receiver and produce a binary value. The signal received at the receiver can be reflected from the object to be detected.

Abstract: The invention relates to a device and method for analysis of a tool (50) e.g. used on a machine tool. A tool detector (5) includes a light emitter (12) and a light receiver (34). Tool (50) when progressed into a beam (20) of light emitted from the emitter (12) will cause a signal from the receiver to change. Circuitry (32) includes a digital signal processor which processes the signal from the receiver and produces an output only if the signal conforms to a predetermined condition. Preferably this predetermined condition could be e.g. a characteristic shape of the signal from the receiver, a change in a value derived from a succession of such signals or a change in the minimum or maximum values of a succession of signals from the receiver.

Abstract: The present invention teaches a method and apparatus for making measurement of an object on a machine, such as a machine tool, using an optical measuring apparatus which includes a light source for generating a beam of light which is incident on a detector. A detection signal is generated within the detector each time the beam is interrupted. The duration and/or frequency of the detection signals are evaluated and an output signal is emitted from the detection only if a further detection signal is present within the detector in a specified time interval from the generation of an earlier detection signal.

Abstract: This invention relates to the detection of tool (50) and other items used on machines by use of a detector (5). An emitter (10) emits a beam of laser light (20) and sensor (30) is used to determine the presence or absence of a tool (50) when the tool is positioned in the beam. If any light is present at the sensor (30) within a predetermined time period then the tool must be broken and the output of the detector is latched. Thus if a broken tool is present and contamination obstructs the beam then this is ignored provided some light is sensed.

Abstract: The invention relates to a measuring device 5 of the type which detects the interruption of a beam of radiation (e.g. light 20) by an object (50 FIG. 1) in the beam. The device includes a light emitter 12 and a light detector 32 each enclosed in a housing 10 and 30. In order to accommodate different spacings between the housings different caps 14 having varying size apertures 11 are fittable to the housings. This allows varying amounts of light to be issued and/or detected. Other ways of adjusting the amount of light passing through the cap are disclosed.