Abstract: An internal defect detection system for a three-dimensional additive manufacturing device which performs additive molding by emitting a laser beam to a powder bed is provided. This system specifies a candidate position of an internal defect on the basis of a change amount of a local temperature measured in an irradiated part of a powder bed irradiated by a laser beam. The system calculates a cooling speed at the candidate position on the basis of a temperature distribution and determines whether an internal defect exists on the basis of the cooling speed.

Abstract: A three-dimensional additive manufacturing device is configured to emit a beam to a powder bed formed by laying a powder on a base plate to harden the powder bed selectively. A sensor is configured to detect the shape or the temperature of a surface of the powder bed or a modeling surface. A defect in laying of the powder or a defect in emission of the beam is corrected based on the detection result, before completion of forming of the next layer.

Abstract: This optical sensor includes an illuminating optical fiber, a first light receiving optical fiber, a second light receiving optical fiber, and a measuring unit. An intersection of a reflected light entering the first light receiving optical fiber and the reflected light entering the second light receiving optical fiber is located on a front end surface of a sensor head or is closer to the peripheral surface of a moving body (a rotating body) than the front end surface of the sensor head is. This can compensate for effects of thermal expansion and accurately measure a clearance.

Abstract: A process abnormality detection system for a three-dimensional additive manufacturing device which performs additive modeling by emitting a beam to a powder bed determines that a laying abnormality of the powder bed is occurring if at least one of a first condition that an average height of the powder bed from a reference position is out of a first predetermined range or a second condition that a height variation of the powder bed is out of a second predetermined range is satisfied, on the basis of a detection result of a shape measurement sensor.

Abstract: A clearance measurement device is a device for measuring a clearance between an inner peripheral surface of a casing and an outer peripheral surface of a rotary body. This device: emits light having a first wavelength and a second wavelength, respectively, towards the outer peripheral surface of the rotary body; receives the light reflected from the outer peripheral surface via a first filter having a transmission band corresponding to the first wavelength and via a second filter having a transmission band corresponding to the second wavelength; and measures the clearance based on a time difference of the moment to detect the rotary body.

Abstract: A three-dimensional additive manufacturing device emits a beam to a powder bed formed by laying a powder on a base plate to harden the powder bed selectively. A sensor detects the shape or the temperature of a surface of the powder bed or a modeling surface. A defect in laying of the powder or a defect in emission of the beam is corrected on the basis of the detection result, before completion of forming of the next layer.

Abstract: A forming defect detection system for a three-dimensional additive manufacturing device which performs additive molding by emitting a laser beam to a powder bed is provided. This system specifies a candidate position of a forming defect on the basis of a change amount of a local temperature measured in an irradiated part of a powder bed irradiated by a laser beam. The system calculates a cooling speed at the candidate position on the basis of a temperature distribution and determines whether a forming defect exists on the basis of the cooling speed.

Abstract: This optical sensor includes an illuminating optical fiber, a first light receiving, optical fiber, a second light receiving optical fiber and a measuring unit. An intersection of a reflected light entering the first light receiving optical fiber and the reflected light entering the second light receiving optical fiber is located on a front end surface of a sensor head or is closer to the peripheral surface of a moving body (a rotating body) than the front end surface of the sensor head is. This can compensate for effects of thermal expansion and accurately measure a clearance.

Abstract: An optical sensor includes an optical fiber disposed in such a way that an end surface thereof is exposed in a distal end surface (10a) of a sensor head (10). The optical sensor includes: a first plate material (first metal plate) (20) in close parallel contact with the distal end surface of the sensor head, and in which a through-hole is formed in a position corresponding to the end surface of the optical fiber; and a second plate material (second metal plate) (30) disposed parallel to the first plate material (first metal plate) and toward the front thereof in a measuring direction, and in which a through-hole is formed at a point of intersection with a virtual straight line perpendicular to the end surface of the optical fiber. With this optical sensor, it is possible for clearance measurement to be performed even if the optical fiber becomes opaque or worn.

Abstract: A process abnormality detection system for a three-dimensional additive manufacturing device which performs additive modeling by emitting a beam to a powder bed determines that a laying abnormality of the powder bed is occurring if at least one of a first condition that an average height of the powder bed from a reference position is out of a first predetermined range or a second condition that a height variation of the powder bed is out of a second predetermined range is satisfied, on the basis of a detection result of a shape measurement sensor.

Abstract: An optical fiber probe includes a probe body, an optical fiber, and a position regulating member. The probe body has a first bottom plate with an outer surface, a second bottom plate opposite to the first bottom, and an internal space. The optical fiber is housed in the internal space. The position regulating member is attached to the probe body. The optical fiber includes a small-diameter portion and a large-diameter portion. The first bottom plate has an inner surface in the internal space and a through hole for communicating the outer surface and the inner surface. The small-diameter portion is inserted into the through hole. The large-diameter portion is arranged such that a first end face thereof is in contact with the inner surface while being bent by the position regulating member in contact with a second end face thereof.

Abstract: A clearance measurement device is a device for measuring a clearance between an inner peripheral surface of a casing and an outer peripheral surface of a rotary body. This device: emits light having a first wavelength and a second wavelength, respectively, towards the outer peripheral surface of the rotary body; receives the light reflected from the outer peripheral surface via a first filter having a transmission band corresponding to the first wavelength and via a second filter having a transmission band corresponding to the second wavelength; and measures the clearance based on a time difference of the moment to detect the rotary body.

Abstract: The present invention includes: a laser that can change the emission wavelength of light; a light-emitting fiber that emits light output from the laser onto a rotor; a concave surface that is provided in a recessed manner in the rotor and reflects the light emitted from the light-emitting fiber; a light-receiving fiber that receives the light reflected by the concave surface; a photodetector that detects the intensity of the light received by the light-receiving fiber; and a control device that controls the laser and performs optical measurement. The intensity is detected by the photodetector while changing the emission wavelength of the laser; the emission wavelength at which the intensity is largest is selected; and optical measurement is performed by detecting the intensity of light reflected by the concave surface by using light having an emission angle determined by the selected emission wavelength.

Abstract: There is provided: a pair of slanted fiber groups; a pair of parallel fiber groups; a light source for emitting two slanted light beams from a pair of slanted light-emitting fibers, and emitting two parallel light beams from a pair of parallel light-emitting fibers; a target provided to the outer peripheral surface of a rotor; a pair of light-receiving elements for detecting the intensity of light received by each of a pair of slanted light-receiving fibers; a pair of light-receiving elements for detecting the intensity of light received by each of a pair of parallel light-receiving fibers; and a computation unit for performing a computation that includes an interval affected by thermal elongation on the basis of four waveforms indicating changes in the intensity detected by each of the light-receiving elements.

Abstract: An optical sensor includes an optical fiber disposed in such a way that an end surface thereof is exposed in a distal end surface (10a) of a sensor head (10). The optical sensor includes: a first plate material (first metal plate) (20) in close parallel contact with the distal end surface of the sensor head, and in which a through-hole is formed in a position corresponding to the end surface of the optical fiber; and a second plate material (second metal plate) (30) disposed parallel to the first plate material (first metal plate) and toward the front thereof in a measuring direction, and in which a through-hole is formed at a point of intersection with a virtual straight line perpendicular to the end surface of the optical fiber. With this optical sensor, it is possible for clearance measurement to be performed even if the optical fiber becomes opaque or worn.

Abstract: The present invention includes: a laser that can change the emission wavelength of light; a light-emitting fiber that emits light output from the laser onto a rotor; a concave surface that is provided in a recessed manner in the rotor and reflects the light emitted from the light-emitting fiber; a light-receiving fiber that receives the light reflected by the concave surface; a photodetector that detects the intensity of the light received by the light-receiving fiber; and a control device that controls the laser and performs optical measurement. The intensity is detected by the photodetector while changing the emission wavelength of the laser; the emission wavelength at which the intensity is largest is selected; and optical measurement is performed by detecting the intensity of light reflected by the concave surface by using light having an emission angle determined by the selected emission wavelength.

Abstract: There is provided: a pair of slanted fiber groups; a pair of parallel fiber groups; a light source for emitting two slanted light beams from a pair of slanted light-emitting fibers, and emitting two parallel light beams from a pair of parallel light-emitting fibers; a target provided to the outer peripheral surface of a rotor; a pair of light-receiving elements for detecting the intensity of light received by each of a pair of slanted light-receiving fibers; a pair of light-receiving elements for detecting the intensity of light received by each of a pair of parallel light-receiving fibers; and a computation unit for performing a computation that includes an interval affected by thermal elongation on the basis of four waveforms indicating changes in the intensity detected by each of the light-receiving elements.

Abstract: An optical fiber probe includes a probe body, an optical fiber, and a position regulating member. The probe body has a first bottom plate with an outer surface, a second bottom plate opposite to the first bottom, and an internal space. The optical fiber is housed in the internal space. The position regulating member is attached to the probe body. The optical fiber includes a small-diameter portion and a large-diameter portion. The first bottom plate has an inner surface in the internal space and a through hole for communicating the outer surface and the inner surface. The small-diameter portion is inserted into the through hole. The large-diameter portion is arranged such that a first end face thereof is in contact with the inner surface while being bent by the position regulating member in contact with a second end face thereof.

Abstract: An exhaust gas analyzer and an exhaust gas analyzing method capable of analyzing the concentration of particulate matter contained in exhaust gas from an internal combustion in real time are provided.

Abstract: An exhaust gas analyzer and an exhaust gas analyzing method capable of analyzing the concentration of particulate matter contained in exhaust gas from an internal combustion in real time are provided.