The Experts below are selected from a list of 279 Experts worldwide ranked by ideXlab platform

Eugenio Dragoni - One of the best experts on this subject based on the ideXlab platform.

  • Optimal design of tapered roller bearings for maximum rating life under combined loads
    Mechanics & Industry, 2016
    Co-Authors: Eugenio Dragoni
    Abstract:

    Using the relationships of the ISO 281 standard, this paper optimizes the internal dimensions of tapered roller bearings for maximum rating life. The bearing system addressed contains two identical bearings subjected to an arbitrary combination of centred radial and axial forces. It is shown that the basic rating life increases more than quadratically with the roller infill and the aspect ratio of the rollers, increases with the sixth power of the Pitch Diameter of the roller set and decreases with the third power of the applied radial force. Further, for any given ratio of axial to radial force, an optimal contact angle exists which maximizes the rating life of the bearing pair, irrespective of the actual bearing size and ratio of roller Diameter to Pitch Diameter. The optimization procedure can either be used to design custom-made bearings or to select from manufacturers’ catalogues the bearing with the best contact angle for any assigned loading condition.

  • Optimal design of paired tapered roller bearings under centred radial and axial static loads
    Mechanics & Industry, 2015
    Co-Authors: Eugenio Dragoni
    Abstract:

    Based on the relationships from the ISO 76 standard, this paper optimizes the internal dimensions of tapered roller bearings for maximum static load capacity. A bearing system formed by two identical bearings is assumed, subjected to whatever combination of centred radial and axial forces. It is shown that the static capacity increases linearly with the roller infill, with the ratio of roller length to roller Diameter and with the square of the Pitch Diameter of the roller set. Further, given the ratio of axial to radial force, an optimal contact angle exists which maximizes the static capacity of the bearing pair, regardless of the actual bearing size and ratio of roller Diameter to Pitch Diameter. The optimization procedure can either be used to design custom-made bearings or to pick from manufacturers’ catalogues the bearing with the best contact angle for any assigned loading condition.

Chih-yen Chen - One of the best experts on this subject based on the ideXlab platform.

  • Real-Time Image-Based Defect Inspection System of Internal Thread for Nut
    IEEE Transactions on Instrumentation and Measurement, 2019
    Co-Authors: Chi-hung Hwang, Chih-yen Chen, Hao-kai Tu, Chun-jen Weng
    Abstract:

    The most important components of the internal nut thread inspection process are measuring the Pitch and Pitch Diameter value and comparing these with their respective specifications, as a test nut is considered to be abnormal when its Pitch or Pitch Diameter does not meet specifications. This paper focuses on defects arising when the Pitch Diameter does not meet its specification. Because conventional contact strategies are not suited to the real-time inspection of internal thread defects, there have been a number of recent attempts to develop noncontact methods for real-time measurement. Some approaches have applied laser triangulation techniques in which reflected light is used to measure the z-axis depth on an object's surface. Although point lasers have been shown to be highly precise in measuring Pitch Diameter, the optical architecture involved in these approaches is complicated and, as the laser must be scanned in a pointwise manner to derive cross-sectional measurements, the measurement process is too long to be compatible with real-time defect inspection. In this papere, an image-based method employing a line laser projector was used to develop a real-time image-based nut Pitch Diameter defect inspection system. The proposed method, which improves upon the conventional, widely used template-matching method for rapid defect detection, was shown to be effective through experimental validation.

  • Real-time Pitch Diameter measurement of internal thread for nut using laser triangulation
    2017 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2017
    Co-Authors: Chi-hung Hwang, Hong-ren Fang, Chih-yen Chen
    Abstract:

    In traditional industrial applications, the thread plug gauge is used to check the Pitch Diameter of the internal thread of a nut. However, the thread plug gauge can only be used to determine whether the nut was manufactured successfully rather than to measure the value of the Pitch Diameter. In recent years, several studies have employed a reflected light method such as laser triangulation to scan the outline of an object. However, most research studies using laser triangulation have developed measurement algorithms for specific objects because the properties of an object's appearance and the reflective laser from that object differ greatly. Existing algorithms are consequently not suitable for scanning the outline of the internal thread of a nut and measuring its Pitch Diameter with laser triangulation. In this paper, we propose a novel, real-time algorithm for measuring the Pitch Diameter of the internal thread of a nut using laser triangulation. First, a specific image preprocessing procedure designed for a reflective laser in the internal thread of a nut is presented. The result of preprocessing critically affects the measurement accuracy of the proposed method. Thereafter, we propose a measurement algorithm designed for the appearance properties of the internal thread of a nut. Our method can operate in real time because the proposed algorithm can measure the Pitch Diameter of the internal thread of a nut in only a few steps and simple calculations.

  • I2MTC - Real-time Pitch Diameter measurement of internal thread for nut using laser triangulation
    2017 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2017
    Co-Authors: Chi-hung Hwang, Hong-ren Fang, Chih-yen Chen
    Abstract:

    In traditional industrial applications, the thread plug gauge is used to check the Pitch Diameter of the internal thread of a nut. However, the thread plug gauge can only be used to determine whether the nut was manufactured successfully rather than to measure the value of the Pitch Diameter. In recent years, several studies have employed a reflected light method such as laser triangulation to scan the outline of an object. However, most research studies using laser triangulation have developed measurement algorithms for specific objects because the properties of an object's appearance and the reflective laser from that object differ greatly. Existing algorithms are consequently not suitable for scanning the outline of the internal thread of a nut and measuring its Pitch Diameter with laser triangulation. In this paper, we propose a novel, real-time algorithm for measuring the Pitch Diameter of the internal thread of a nut using laser triangulation. First, a specific image preprocessing procedure designed for a reflective laser in the internal thread of a nut is presented. The result of preprocessing critically affects the measurement accuracy of the proposed method. Thereafter, we propose a measurement algorithm designed for the appearance properties of the internal thread of a nut. Our method can operate in real time because the proposed algorithm can measure the Pitch Diameter of the internal thread of a nut in only a few steps and simple calculations.

H.h Mabie - One of the best experts on this subject based on the ideXlab platform.

  • Determination of pinion-cutter offsets required to produce nonstandard spur gears with teeth of equal strength
    Mechanism and Machine Theory, 2003
    Co-Authors: R.n. Green, H.h Mabie
    Abstract:

    Abstract This paper presents a method of designing nonstandard spur gears cut with a pinion cutter so that the static bending stresses in the pinion teeth and in the gear teeth are approximately equal. Consideration was limited to gear pairs which would operate with zero backlash and which could be cut using standard Fellows-type cutters. Design charts are presented from which cutter offsets can be determined for various gear ratios, for changes in center distance, and for a particular diametral Pitch and Pitch Diameter of cutter.

  • Determination of static tooth stresses in nonstandard spur gears cut by pinion cutter
    Mechanism and Machine Theory, 2003
    Co-Authors: R.n. Green, H.h Mabie
    Abstract:

    Abstract This paper is a continuation of the paper entitled “Determination of Pinion-Cutter Offsets Required to Produce Nonstandard Spur Gears with Teeth of Equal Strength.” Sample charts are presented for determining how closely the static bending stress in the pinion teeth and gear teeth are balanced when gears are designed using the cutter offsets determined from the previous paper. These charts are plots of stress factors for the pinion or gear versus gear ratio for changes in center distance and for a particular diametral Pitch and Pitch Diameter of cutter. This paper also presents a set of sample calculations for the determination of the stresses in the pinion teeth and gear teeth.

Chi-hung Hwang - One of the best experts on this subject based on the ideXlab platform.

  • Real-Time Image-Based Defect Inspection System of Internal Thread for Nut
    IEEE Transactions on Instrumentation and Measurement, 2019
    Co-Authors: Chi-hung Hwang, Chih-yen Chen, Hao-kai Tu, Chun-jen Weng
    Abstract:

    The most important components of the internal nut thread inspection process are measuring the Pitch and Pitch Diameter value and comparing these with their respective specifications, as a test nut is considered to be abnormal when its Pitch or Pitch Diameter does not meet specifications. This paper focuses on defects arising when the Pitch Diameter does not meet its specification. Because conventional contact strategies are not suited to the real-time inspection of internal thread defects, there have been a number of recent attempts to develop noncontact methods for real-time measurement. Some approaches have applied laser triangulation techniques in which reflected light is used to measure the z-axis depth on an object's surface. Although point lasers have been shown to be highly precise in measuring Pitch Diameter, the optical architecture involved in these approaches is complicated and, as the laser must be scanned in a pointwise manner to derive cross-sectional measurements, the measurement process is too long to be compatible with real-time defect inspection. In this papere, an image-based method employing a line laser projector was used to develop a real-time image-based nut Pitch Diameter defect inspection system. The proposed method, which improves upon the conventional, widely used template-matching method for rapid defect detection, was shown to be effective through experimental validation.

  • Real-time Pitch Diameter measurement of internal thread for nut using laser triangulation
    2017 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2017
    Co-Authors: Chi-hung Hwang, Hong-ren Fang, Chih-yen Chen
    Abstract:

    In traditional industrial applications, the thread plug gauge is used to check the Pitch Diameter of the internal thread of a nut. However, the thread plug gauge can only be used to determine whether the nut was manufactured successfully rather than to measure the value of the Pitch Diameter. In recent years, several studies have employed a reflected light method such as laser triangulation to scan the outline of an object. However, most research studies using laser triangulation have developed measurement algorithms for specific objects because the properties of an object's appearance and the reflective laser from that object differ greatly. Existing algorithms are consequently not suitable for scanning the outline of the internal thread of a nut and measuring its Pitch Diameter with laser triangulation. In this paper, we propose a novel, real-time algorithm for measuring the Pitch Diameter of the internal thread of a nut using laser triangulation. First, a specific image preprocessing procedure designed for a reflective laser in the internal thread of a nut is presented. The result of preprocessing critically affects the measurement accuracy of the proposed method. Thereafter, we propose a measurement algorithm designed for the appearance properties of the internal thread of a nut. Our method can operate in real time because the proposed algorithm can measure the Pitch Diameter of the internal thread of a nut in only a few steps and simple calculations.

  • I2MTC - Real-time Pitch Diameter measurement of internal thread for nut using laser triangulation
    2017 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2017
    Co-Authors: Chi-hung Hwang, Hong-ren Fang, Chih-yen Chen
    Abstract:

    In traditional industrial applications, the thread plug gauge is used to check the Pitch Diameter of the internal thread of a nut. However, the thread plug gauge can only be used to determine whether the nut was manufactured successfully rather than to measure the value of the Pitch Diameter. In recent years, several studies have employed a reflected light method such as laser triangulation to scan the outline of an object. However, most research studies using laser triangulation have developed measurement algorithms for specific objects because the properties of an object's appearance and the reflective laser from that object differ greatly. Existing algorithms are consequently not suitable for scanning the outline of the internal thread of a nut and measuring its Pitch Diameter with laser triangulation. In this paper, we propose a novel, real-time algorithm for measuring the Pitch Diameter of the internal thread of a nut using laser triangulation. First, a specific image preprocessing procedure designed for a reflective laser in the internal thread of a nut is presented. The result of preprocessing critically affects the measurement accuracy of the proposed method. Thereafter, we propose a measurement algorithm designed for the appearance properties of the internal thread of a nut. Our method can operate in real time because the proposed algorithm can measure the Pitch Diameter of the internal thread of a nut in only a few steps and simple calculations.

Lu Yonghua - One of the best experts on this subject based on the ideXlab platform.

  • a new compensation method for measurement of thread Pitch Diameter by profile scanning
    Measurement Science Review, 2014
    Co-Authors: Chen Sheng, Zhao Dongbiao, Lu Yonghua
    Abstract:

    For measurement of existing thread parameters using profile scanning, system error increases as Pitch Diameter, difference between the calibrating thread and measuring thread increases with the single gauge calibration method. There are several alignment deviations affecting the measurement of Pitch Diameter. To reduce the system error, a compensation method using two standard thread gauges to calculate the alignment deviations is proposed here. Finally, the theoretical and experimental comparisons between the single gauge calibration method and the proposed method are presented. The results demonstrate that the two gauges calibration method can effectively reduce the system error.