Abstract: An improved method is described for measuring a dimension (e.g. diameter) of a non-toothed tool, for example a grinding tool such as a diamond coated burr. The method may be implemented on a machine tool, such as a lathe, machining centre or the like. The method comprises passing a beam of light from a transmitter to a receiver. The receiver produces a received intensity signal related to the intensity of received light. Analysis of variations in the received intensity signal is performed when a rotating tool is moved relative to the light beam to enable a dimension of the tool to be measured. In particular, it may be determined when the received intensity signal has crossed a threshold for at least a defined duration, the defined duration being less than the time taken for one complete rotation of the tool.

Abstract: A method assesses the beam profile of a light beam of a non-contact tool setting apparatus, the apparatus including a transmitter for emitting the light beam and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The apparatus is mounted to a machine tool having a spindle that is moveable relative to the non-contact tool setting apparatus. The method includes loading an object having an edge into the spindle of the machine tool and using the machine tool to move the spindle relative to the apparatus so that the edge of the object passes through the light beam. The beam profile of the light beam is then determined using the beam intensity signal generated at a plurality of positions during the step (ii) of moving the edge of the object through the light beam.

Abstract: A measurement apparatus for mounting within an enclosure of a machine is described. The apparatus includes a measurement device and a protection means for protecting the measurement device from contaminants present within the machine enclosure. The protection means is switchable between at least a first mode that protects the measurement device from contaminants and a second mode that provides less protection of the measurement device from contaminants than the first mode. A contaminant sensor is used for sensing contamination within the machine enclosure and thereby determining when the protection means can adopt the second mode. A corresponding method is also described.

Abstract: A method for tool measurement using a non-contact tool setting apparatus mounted to a machine tool, which includes a transmitter for emitting a light beam having a beam width and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The method is for measuring a tool having a nominal tool diameter less than the beam width so fully inserting the tool feature into the light beam would only partially occlude the beam. The method includes moving the tool through the beam thereby causing a change in the intensity signal and generating a trigger signal when the intensity signal crosses a trigger threshold. The tool size is derived using the trigger signal generated. Also, a step of applying a tool length correction that accounts for the nominal tool diameter of the tool being less than the beam width.

Abstract: A method for tool measurement using a non-contact tool setting apparatus mounted to a machine tool, which includes a transmitter for emitting a light beam having a beam width and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The method is for measuring a tool having a nominal tool diameter less than the beam width so fully inserting the tool feature into the light beam would only partially occlude the beam. The method includes moving the tool through the beam thereby causing a change in the intensity signal and generating a trigger signal when the intensity signal crosses a trigger threshold. The tool size is derived using the trigger signal generated. Also, a step of applying a tool length correction that accounts for the nominal tool diameter of the tool being less than the beam width.

Abstract: A method assesses the beam profile of a light beam of a non-contact tool setting apparatus, the apparatus including a transmitter for emitting the light beam and a receiver for receiving the light beam. The receiver generates a beam intensity signal describing the intensity of received light. The apparatus is mounted to a machine tool having a spindle that is moveable relative to the non-contact tool setting apparatus. The method includes loading an object having an edge into the spindle of the machine tool and using the machine tool to move the spindle relative to the apparatus so that the edge of the object passes through the light beam. The beam profile of the light beam is then determined using the beam intensity signal generated at a plurality of positions during the step (ii) of moving the edge of the object through the light beam.

Abstract: A tool setting or tool analysis device for a machine tool includes a light source for producing a light beam. A light receiver receives the light beam and produces a signal indicative of the amount of light received. This is analyzed by a main analysis circuit to generate a trigger signal to a machine controller when the beam is at least partially occluded. To provide fail-safe operation should the main circuit not recognize the tool, a back-up trigger signal is produced after a delay by a delay circuit. In one preferred form, the back-up trigger signal may oscillate, providing repeated edges which can ensure fail-safe operation even if the machine controller suffers from a blind window and therefore misses the initial trigger signal.

Abstract: A tool setting or tool analysis device for a machine tool includes a light source for producing a light beam. A light receiver receives the light beam and produces a signal indicative of the amount of light received. This is analysed by a main analysis circuit to generate a trigger signal to a machine controller when the beam is at least partially occluded. To provide fail-safe operation should the main circuit not recognise the tool, a back-up trigger signal is produced after a delay by a delay circuit. In one preferred form, the back-up trigger signal may oscillate, providing repeated edges which can ensure fail-safe operation even if the machine controller suffers from a blind window and therefore misses the initial trigger signal.

Abstract: An object detector apparatus. The object detector apparatus comprises a receiver which is configured to receive a signal from an object having a repetitive motion, in which the signal repeats at a frequency that is dependent on the frequency of the repetitive motion of the object. The object detector apparatus further comprises an analyzer which is configured to sample a signal received by the receiver according to a first set of sampling parameters into a first sampled data set, and to produce an output based on a comparison of the first sampled data set with at least one previously sampled data set. The analyzer is also operable to sample a signal received by the receiver using a second set of sampling parameters which differs to the first set of sampling parameters into a second sampled data set, and to produce an output based on a comparison of the second sampled data set with at least one previously sampled data set.

Abstract: A tool setting or tool analysis device for a machine tool comprises a light source for producing a light beam. A light receiver receives the light beam and produces a signal indicative of the amount of light received. This is analyzed by a main analysis circuit to generate a trigger signal to a machine controller when the beam is at least partially occluded. To provide fail-safe operation should the main circuit not recognize the tool, a back-up trigger signal is produced after a delay by a delay circuit. In one preferred form, the back-up trigger signal may oscillate, providing repeated edges which can ensure fail-safe operation even if the machine controller suffers from a blind window and therefore misses the initial trigger signal.

Abstract: A tool setting or tool analysis device for a machine tool comprises a light source for producing a light beam. A light receiver receives the light beam and produces a signal indicative of the amount of light received. This is analyzed by a main analysis circuit to generate a trigger signal to a machine controller when the beam is at least partially occluded. To provide fail-safe operation should the main circuit not recognize the tool, a back-up trigger signal is produced after a delay by a delay circuit. In one preferred form, the back-up trigger signal may oscillate, providing repeated edges which can ensure fail-safe operation even if the machine controller suffers from a blind window and therefore misses the initial trigger signal.

Abstract: An object detector apparatus. The object detector apparatus comprises a receiver which is configured to receive a signal from an object having a repetitive motion, in which the signal repeats at a frequency that is dependent on the frequency of the repetitive motion of the object. The object detector apparatus further comprises an analyser which is configured to sample a signal received by the receiver according to a first set of sampling parameters into a first sampled data set, and to produce an output based on a comparison of the first sampled data set with at least one previously sampled data set. The analyser is also operable to sample a signal received by the receiver using a second set of sampling parameters which differs to the first set of sampling parameters into a second sampled data set, and to produce an output based on a comparison of the second sampled data set with at least one previously sampled data set.