Gear Inspection Research Articles

Laser Interferometric Measuring Method of Involute Artifact and Stabilization of Measurement

Vibration and noise are serious problems with involute spur and helical gears used, e.g., in drivetrains of vehicles such as automobiles. The gear tooth flank form of micrometer order markedly affects gear vibration and noise; therefore, the tooth flank form quality must be strictly controlled to maximize gear performance. Tooth profile measuring machines used in calibration for form error inspection of involute gears usually use an involute artifact, which itself must be calibrated highly accurately. However, it is typically difficult for current tooth profile measuring machine using contact stylus to calibrate the involute artifact with a high accuracy while satisfying traceability to a national standard. A highly precise and traceable measuring technology for the involute artifact is therefore required. The direct measurement of the involute artifact we propose uses a laser interferometer, whose measurement stability is confirmed in experiments measuring the detailed form of an involute tooth flank.

The Research on the Application to Digital Image Technology in Hypoid Gear Contact Zone Detection

The method is to gain the image of tooth profile and contact spot by using digital camera, to reconstruct diametrically the contact spot of hypoid gear through the computer graphics techniques, to make sure of the relative position on the edges between tooth surface and spot, and to evaluate the size, position and direction of contact spot, in order to provide foundation for in-line inspection of gear.

Research on Detection of Micro Plastic Gear Tooth Based on Dummy Circle Scan Method

The quality of micro plastic gears was inspected with the image recognition technology herein. Focusing on the situation that gears’ defects were uncertain, the construction of computer vision system and the theories, technologies of digital image acquisition, image preprocessing, image segmentation as well as the sub-pixel location theory were studied thoroughly. A dummy circle scan method is presented to realize the gear tooth inspection, and the results indicate that it can meet request on the automatic inspection of micro plastic gears.

생산라인용 자동차 변속기용 헬리컬 기어 검사 장치에 관한 연구

본 논문은 자동차 변속기의 헬리컬기어 검사 장치에 대한 것이다. 기어 프로파일 전용 검사설비는 시간이 많이 소요되므로 생산라인용으로 적합하지 못하다. 본 논문에서 사용된 마스트기어를 이용하여 생산된 기어와 비교하여 방법은 보다 경제적이며 효율적이다. 본 논문에 사용된 3가지 기어검사 파라미터는 nick, 흔들림(run-out) 및 PCD (pitch circle diameter) 등이다. 기어검사장치의 측정정밀도에 영향을 미치는 요소들에 대해서도 또한 언급되었다. 이 장치는 현재 국내에서 전량 수입되는 기어 생산라인용 설비에 실제적으로 사용될 것이다.

Flexible RollScann-design of one-tooth-roll-master and simulations for data acquisition

The recent improvements in the design and production of gears are not matched by the improvements in the development of measuring techniques and evaluation standards which can, in short time, give precise information about the quality of the produced gear. The inspection of gears with tooth flank modifications is still conducted by measuring of the profile and flank lines, pitch and concentricity. Furthermore topographical measurement on the coordinate measuring machine is an expensive and lasting process. This paper presents the development of a new, flexible gear-measuring machine called RollScan, which can measure the entire gear topography in a few minutes and can be introduced directly into the production line. For this, a machine with four axes and the control, a new one tooth roll master and evaluation software is designed, which makes the machine flexible and enables a variety of gear measurements without any special mechanical adjustments.

Digital Precision Measuring of Spiral Bevel Gear Based on CAD/CAM/CMM

Precision measuring techniques have been developed interdependently with the techniques of design and manufacturing in the history. Computer aided inspection plays a very important role in modern manufacturing industry. On account of the CMM (Coordinates Measurement Machine) being applied widely and the precision model inspection concept coming true, it is possible to implement the digital inspection of the spiral bevel gear on the CMM. In this paper the framework of the spiral bevel gear digital inspection based on the integration of CAD/CAM/CMM is put forward. The key techniques of the scheme are investigated, which consist of exact modeling of spiral bevel gear based on manufacturing process, datum matching of CAD model and CMM inspection, CMM Inspection path planning, reconstruction of the tooth surface based on the CMM inspection results, Analysis of the deviation between the real gear tooth and CAD model, adjusting strategy of machining parameters.

New design method for hypoid gears

A digital model is presented for the purpose of design, manufacture and measurement of hypoid gear, based on the non-uniform rational B-spline surface (NURBS) method. The digital model and the function-oriented active design technique are combined to form a new design method for hypoid gears. The method is well adaptable to CNC bevel gear cutting machines and CNC-controlled gear inspection machines, and can be used to create the initial machine tool cutting location data or program measurement path. The presented example verifies the method is correct.

人工知能を用いたハイポイド歯車の歯当り評価システムの開発 : 歯当り画像の評価(O.S.04-1 歯車の検査(1),O.S.08-2 ハイポイド・ウォーム(1))

Tooth Bearing is commonly used for hypoid gear pair inspection. Usually, in the inspection, hyipoid gear pairs are qualitatively evaluated by OK / NG. However, in order to conduct a follow-up survey on bad quality of products, quantitative evaluation of tooth bearing could be effective. For this purpose, the tooth bearing is inspected and evaluated by the experienced technicians. In the present study, a computer evaluation system for tooth bearing of hypoid gear pair has been developed. It is based on the nueral net, and enables the results of the inspections to be evaluated instead of the experienced technicians. The present paper describes the comparison of system evaluations with the technitian's ones. As a result, the evaluation performance of the developed system was greatly affected by quality of tooth bearings which are used for teacher signals.

GEAR MACHINING AND INSPECTION BY CNC MACHINES WITHOUT ROTARY TABLE

GEAR MACHINING AND INSPECTION BY CNC MACHINES WITHOUT ROTARY TABLE

Gear Metrology

Gear drives represent key components for all kind of vehicles, machine tools, aircrafts, household appliances as well as a broad variety of industrial equipment and toys. The designers are confronted with increasing demands concerning lifetime, power transmission and noise emission, whereas the size and weight of gear drives is constantly reduced. Thus, the measurement of gears and gear tools is of decisive importance for gear production. This paper reviews the state-of-the-art of gear metrology, where tactile probing methods dominate almost exclusively. It summarizes new modelling and measuring principles, enabling a superficial description and inspection of gears. Especially optical measuring methods, the inspection of micro gears and alignment problems are discussed in detail. A final section reports the actual accuracy limits of gear measurements. It points out that a significant reduction of the measuring uncertainty associated with gears, standards and instruments is an urgent need for the production of high-precision gears.

804 片歯面かみあい試験機による歯面修整歯車の精度評価

804 片歯面かみあい試験機による歯面修整歯車の精度評価

Development of a novel lead master consisting of an offset sphere

During the calibration of gear inspection systems, special calibration masters, or artifacts, are often used. Lead masters are used for adjustment and calibration of the system’s lead generation axes and algorithms. This paper discusses the development of a novel lead master for system calibration consisting of an offset sphere. A curve along the surface of the sphere is used to simulate a helix. The calibration curve for the artifact is formulated. Critical design parameters are specified. In addition, the impact to the calibration curve attributable to measurement uncertainties for the design parameters is assessed. An example design is also presented.

Coastal management in Tanga, Tanzania: a decentralized community-based approach

This paper describes a new initiative in coastal management in northeastern Tanzania. The region is within the equatorial part of the Western Indian Ocean. The priority environmental issues being faced include declining fish catches, use of destructive fishing techniques, mangrove cutting and coastal erosion. There is a widespread perception among the users of the coastal resources that management of these issues is inadequate. This programme initiative is developing flexible, community-based approaches to identifying the problems and to take achievable actions. The programme provides training in a wide range of skills and appropriate technical methods for government officials, extension workers and villagers. A collaborative process is evolving that includes participatory appraisals, village environmental committees, facilitation by government extension workers, technical advise and supervision by district technical teams, and regional-wide workshops with key players. Village initiatives taken so far include new by-laws, gear inspection, reef zoning and closures. A number of village mariculture projects are being piloted.

The accuracy of image analysis methods in spur gear metrology

This paper describes the design of an involute spur gear inspection system in which measurements are made using a video camera and image analysis software. The measurement accuracy possible using low-cost CCTV cameras is investigated, and the possible sources of error identified. It is concluded that the measurement accuracy is comparable to that of current methods for tolerance inspection of spur gears and the low cost and ease of use make image analysis measurement systems an attractive alternative.

Encyclopedic dictionary of gears and gearing

Gear Geometry. Gear Types. Gear Materials and Heat Treatments. Load Rating and Design of Gears and Selection of Gear Drives. Inspection and Testing of Gears and Gear Materials. Gear Tooth Wear and Failure. Lubrication of Open and Closed Gear Drives. Splines. Enclosed Gear Drives. Gear Manufacturing Equipment and Manufacturing Methods. Gear Cutting Tools. Machine Tool Mechanics. Mechanical Engineering. General Information.

Computerized Analysis of Gear Meshing Based on Coordinate Measurement Data

A mathematical model is proposed for the reconstruction of gear tooth surface features based on the manufacturing process deviations measured with the help of a gear inspection (or coordinate measurement) machine. The model is extended to facilitate the computer simulation of meshing between the measured gear and a theoretical master gear, or between two measured gears. This would allow one to predict the transmission errors and bearing contact which are otherwise only possible to investigate using the combination of single-flank testing and a time-consuming work-in and examination procedure. The developed model is applied to the determination of tooth-to-tooth transmission errors of parallel-axis gears and can also be utilized to determine bearing contact and contact stresses and be useful in tooth surface fatigue life calculations.

MAIN REDUCTION GEAR OVERHAUL

ABSTRACTMain reduction gears are considered by many to be mystical with no preventative maintenance necessary or desirable other than oil and filter changes. This is, of course, not the case.The intent of this article is to furnish the reader with a general description of a Main Reduction Gear Inspection and Overhaul. Although the article specifically details two major overhauls on Western Gears of U.S. Coast Guard HAMILTON Class Cutters, i.e., BOUTWELL, (WHEC‐719) and MUNRO (WHEC‐724), it contains pertinent inspection and overhaul information for many types of main reduction gears and most propeller shafting arrangements.The article should leave the reader with a better understanding of what is really involved in a reduction gear inspection and overhaul. Some of the avoidable pitfalls will be addressed and a lot of helpful hints will be aired.

A Novel Approach To The Inspection Of GearsWith A Co-ordinate Measuring Machine -Theoretical Aspects

The accuracy of gears is a key to the performance of a mechanical transmission system. In this paper a novel approach is proposed for inspecting gear profiles with a Co-ordinate Measuring Machine (CMM). The gear profile inspection models are described with a set of equations. The theoretical aspects of the models are explored with respect to the minimum number of inspection points, profile evaluation method and the factors influencing the inspection accuracy. The co-ordinates of a certain number of points on the gear tooth surface are measured and a theoretical gear tooth surface expressed as a function of the CMM co-ordinate system is estimated by the method of least squares, so that the surface fits the measured data. The gear profile models and their simulations are implemented via MATLAB.

The Measurement Of Involute Worm Wheels

This paper describes the traditional methods used for checking worm gears, using contact marking techniques and discusses a new method for the analytical measurement of worm gears which uses a CNC gear inspection machine at the UK National Gear Metrology laboratory. Some of the development and validation problems are discussed and example measurement results are given. 1.0 Introduction and Background Equipment, standards and procedures for the measuring of involute spur and helical gears have been available for many years. During this time, manufacturers of involute worm gears, although an important part of the transmission business, have not had this luxury because the geometry of involute worm gears is far more complex than involute spur and helical gears. A typical worm gear pair is shown in Fig. 1. The development of analytical inspection techniques could not be implemented until CMMs or CNC machines, with sufficiently powerful computers became available. 1.1 Conventional Contact Marking Inspection Procedure The involute worm is an accurate screw thread with an involute profile and it is relatively simple to measure. Standard gear inspection machines or CNC gear checking machines may be used with acceptable accuracy. The worm wheel is far more complex. It is not feasible to build a mechanical inspection machine for checking worm wheels. Worm wheel manufacturers have traditionally used a contact marking test procedure, as outlined below: Transactions on Engineering Sciences vol 16, © 1997 WIT Press, www.witpress.com, ISSN 1743-3533

CNC Gear Inspection Technology And NewSoftware Solutions Adapted To IndividualIndustry Needs

The requirements on gearing have steadily increased over the past years. On the one hand, increasingly more compact gear units with greater power density are required, while on the other hand high demands on operating behaviour and efficiency must often be met. All this means that gearing with top quality and low tolerance levels must be produced in both low and high volumes. Moreover, this gearing must often be produced with precisely defined flank modifications in order to achieve the desired characteristics. Gearing measurement technology has become a crucial aid in production, in order to create particular parameters and to ensure that they will be maintained during the manufacturing process. The design and functioning of appropriate testing machines will be described in the presentation. The conceptual design is explained in reference to the individual measuring tasks, and the most important components of the testing machine, such as drive systems, probe systems, control and computer systems are described. The second part of the presentation treats software as well as practical measurement examples in the areas of software management, operator guidance, evaluation and documentation of measurement results, examples of measurement times, measurement accuracy and the introduction of new software for the analytic evaluation of a gear set. By means of the gear contact analysis of a gear set, the combined effect of gear and pinion is simulated on the computer on the basis of individual profile and alignment measurements. Transactions on Engineering Sciences vol 23, © 1999 WIT Press, www.witpress.com, ISSN 1743-3533