Abstract: An information terminal is configured to extract a predetermined frequency band from a waveform of a signal of a machine component detected by a vibration sensor, to compare an analyzed frequency component and a damaging frequency resulting from a damage of the machine component, and to diagnose abnormality of the machine component. The information terminal includes a database in which the damaging frequency resulting from the damage of the machine component is preserved as a converted damaging frequency obtained by converting the damaging frequency on a basis of a predetermined rotating speed of the machine component. The damaging frequency is provided by calculating the converted damaging frequency in the database by using an actual rotating speed of the machine component. Accordingly, it is possible to keep specifications of a machine component confidential without preserving the specifications of the machine component.

Abstract: A vibration analyzer is configured to analyze vibration of a machine component and which is capable of performing an operation on a basis of a signal received from an information terminal and transmitting a signal obtained as a result of the operation to the information terminal. The vibration analyzer includes a vibration sensor configured to detect a vibration of the machine component, a filter processing unit configured to extract a predetermined frequency band from a waveform of a signal detected by the vibration sensor, and a calculation processing unit configured to analyze frequency of a waveform after filter processing obtained by the filter processing unit and to obtain spectrum data. Accordingly, it is possible to reduce a data amount to be transmitted between the analyzer and the information terminal, thereby shortening data transfer time.

Abstract: An abnormal noise detection method of a steering system is configured to detect an abnormal noise from the steering system. The steering system includes a column shaft configured to rotatably support a steering wheel and is configured to steer a wheel in response to rotations of the column shaft. The method includes measuring a sound from an end portion of the column shaft on a steering wheel-side by using a microphone arranged to face the end portion of the column shaft, and generating an abnormal noise detection signal due to the steering system from a sound signal to be output from the microphone.

Abstract: An information terminal is configured to extract a predetermined frequency band from a waveform of a signal of a machine component detected by a vibration sensor, to compare an analyzed frequency component and a damaging frequency resulting from a damage of the machine component, and to diagnose abnormality of the machine component. The information terminal includes a database in which the damaging frequency resulting from the damage of the machine component is preserved as a converted damaging frequency obtained by converting the damaging frequency on a basis of a predetermined rotating speed of the machine component. The damaging frequency is provided by calculating the converted damaging frequency in the database by using an actual rotating speed of the machine component. Accordingly, it is possible to keep specifications of a machine component confidential without preserving the specifications of the machine component.

Abstract: An information terminal is configured to extract a predetermined frequency band from a waveform of a signal of a machine component detected by a vibration sensor, to compare an analyzed frequency component and a damaging frequency resulting from a damage of the machine component, and to diagnose abnormality of the machine component. The information terminal includes a database in which the damaging frequency resulting from the damage of the machine component is preserved as a converted damaging frequency obtained by converting the damaging frequency on a basis of a predetermined rotating speed of the machine component. The damaging frequency is provided by calculating the converted damaging frequency in the database by using an actual rotating speed of the machine component. Accordingly, it is possible to keep specifications of a machine component confidential without preserving the specifications of the machine component.

Abstract: A vibration analyzer is configured to analyze vibration of a machine component and which is capable of performing an operation on a basis of a signal received from an information terminal and transmitting a signal obtained as a result of the operation to the information terminal. The vibration analyzer includes a vibration sensor configured to detect a vibration of the machine component, a filter processing unit configured to extract a predetermined frequency band from a waveform of a signal detected by the vibration sensor, and a calculation processing unit configured to analyze frequency of a waveform after filter processing obtained by the filter processing unit and to obtain spectrum data. Accordingly, it is possible to reduce a data amount to be transmitted between the analyzer and the information terminal, thereby shortening data transfer time.

Abstract: An abnormal noise detection method of a steering system is configured to detect an abnormal noise from the steering system. The steering system includes a column shaft configured to rotatably support a steering wheel and is configured to steer a wheel in response to rotations of the column shaft. The method includes measuring a sound from an end portion of the column shaft on a steering wheel-side by using a microphone arranged to face the end portion of the column shaft, and generating an abnormal noise detection signal due to the steering system from a sound signal to be output from the microphone.

Abstract: A reactor core cooling structure of the present invention comprises cooling gas flow-in slits for making a cooling gas flow in a circular reactor core, which slits are provided at an outer graphite cylinder for covering an outside of the circular reactor core; cooling gas flow-out slits for making the cooling gas flow in a circular reactor core, which slits are provided at an inner graphite cylinder for covering an inside of the circular reactor core; a circular cooling gas flow path that is provided at an outside of the outer graphite cylinder, and is connected to an inlet piping of the cooling gas at a foot of the outer graphite cylinder; and an inner cooling gas flow path that is provided at an inside of the inner graphite cylinder, and is connected to an outlet piping of the cooling gas at a foot of the inner graphite cylinder.

Abstract: A reactor core cooling structure of the present invention comprises cooling gas flow-in slits for making a cooling gas flow in a circular reactor core, which slits are provided at an outer graphite cylinder for covering an outside of the circular reactor core; cooling gas flow-out slits for making the cooling gas flow in a circular reactor core, which slits are provided at an inner graphite cylinder for covering an inside of the circular reactor core; a circular cooling gas flow path that is provided at an outside of the outer graphite cylinder, and is connected to an inlet piping of the cooling gas at a foot of the outer graphite cylinder; and an inner cooling gas flow path that is provided at an inside of the inner graphite cylinder, and is connected to an outlet piping of the cooling gas at a foot of the inner graphite cylinder.

Abstract: The frequencies generated based on the undulations existing on the inner and outer ring raceways 8, 10 and on the rolling surface of the balls 11, 11 are out of coincidence with the rotational frequency itself of the rotation member supported by the rolling bearing, and with a frequency component which is a multiple of the rotational frequency, or kinds of frequencies generated due to the undulations are out of coincidence with each other in the natural frequency domain of a rotation system which is a rotation supporting portion having the rolling bearing incorporated therein, whereby without using a special grease, the self-excited frequency of the rolling bodies hardly grows to abnormal vibration, and a rolling bearing having sufficient durability and causing no abnormal vibration and noise even if used at low temperature is realized.

Abstract: A surface shape evaluation method for a spherical body comprising the steps of: providing a support hole having a smaller diameter than the spherical body and having a curved bearing surface formed on its opening to have a curvature substantially equal to the curvature of the surface of the spherical body, providing a rotation drive arm for transmitting only a rotation component to the spherical body, providing a vibration sensor having a probe with a flat tip end, rotating the spherical body on a predetermined center axis and on the opening, such that one portion in the radial direction of the spherical body comes into contact with the curved bearing surface while the portion opposite to the one portion in the radial direction of the spherical body comes into contact with the tip end of the rotation drive arm, abutting the flat tip end of the probe of the vibration sensor to a surface portion of the spherical body located on a hypothetical flat surface which is orthogonal to the center axis and passes throug

Abstract: A rolling bearing unit having undulation on the rolling surfaces of the rolling elements where the total value of the wave components having an even number of waves per circumference is smaller than the total value of the wave components having an odd number of waves per circumference, or having undulation on the inner ring raceway and outer ring raceway, where the undulation on at least one of the raceway is conditioned such that the maximum waviness amplitude among (nZ), (nZ+1) and (nZ -1) waves per circumference is smaller than the maximum waviness amplitude among (nZ+2) and more waves per circumference, where n is a positive integer and Z is the number of rolling elements, thereby making it possible to obtain a low-cost, high-performance rolling bearing in which the vibration characteristics of the rolling bearing are improved without having to increase the precision required for manufacturing the rolling elements and inner ring raceway and outer ring raceways.