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Article
Publication date: 1 March 1999

Hiroshi Makino

Smart cam or electronic cam is a combination of a computer program for motion definition and a high‐performance servo mechanism. By using this, one can obtain a…

Abstract

Smart cam or electronic cam is a combination of a computer program for motion definition and a high‐performance servo mechanism. By using this, one can obtain a high‐speed, reliable and application‐oriented motion, just as obtained from a mechanical cam system. Hard cams are dedicated and difficult to change, but smart cams are flexible in stroke, in timing, etc. With the progress of computer and servo technology, smart cams are becoming widely used. In this report the methods used to create smart cams are discussed and some examples are shown. The experimental results of these examples show excellent performance which is as good as hard cams.

Details

Assembly Automation, vol. 19 no. 1
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 9 March 2015

Wenjie Qin and Lunjing Duan

This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of…

Abstract

Purpose

This paper aims to present the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of elastohydrodynamic lubrication (EHL), according to the cam wear prediction using Archard’s model. Cam–follower kinematic pairs always work under wear because of concentrated contacts. Given that a cam and follower contact often operates in the mixed or boundary lubrication regime, simulation of cam wear is a multidisciplinary problem including kinematic considerations, dynamic load and stress calculations and elastohydrodynamic film thickness evaluations.

Design/methodology/approach

Multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL are applied to obtain the dynamic loads, the time histories of contact pressure and the oil film thicknesses in cam–follower conjunctions to predict cam wear quantitatively.

Findings

The wear depth of the cam in the valve train of a heavy-load diesel engine is calculated, which is in good agreement with the measured value in the practical test. The results show that the cam–tappet pair operates under a mixed lubrication or boundary lubrication, and the wear depths on both sides of the cam nose are extremely great. The wear of these points can be decreased significantly by modifying the local cam profile to enlarge the radii of curvature.

Originality/value

The main value of this work lies in the model and method involving multi-body system dynamic analysis, finite element quasi-statics contact analysis and numerical calculation of EHL, which can give good prediction for the wear of cam.

Details

Industrial Lubrication and Tribology, vol. 67 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 March 1999

Mike Woelfel

Introduces the reader to the concepts and benefits of electronic cam capability in electronic motion control systems. General mechanical cam operation is discussed and the…

Abstract

Introduces the reader to the concepts and benefits of electronic cam capability in electronic motion control systems. General mechanical cam operation is discussed and the concept of electronic cam is described. A “rotary knife” application is used to illustrate how electronic cam can increase the quality of motion and simplify programming.

Details

Assembly Automation, vol. 19 no. 1
Type: Research Article
ISSN: 0144-5154

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Book part
Publication date: 24 September 2010

Georgiana Bostean

Immigrants’ access to health services is a widely researched topic, yet few studies examine immigrants’ use of complementary and alternative medicine (CAM). This study…

Abstract

Immigrants’ access to health services is a widely researched topic, yet few studies examine immigrants’ use of complementary and alternative medicine (CAM). This study uses the Behavioral Model to compare overall CAM use and use of acupuncture, chiropractic, herbs, yoga, and relaxation by immigrant status (nativity and time in the United States). It then explains the nativity gap in use by assessing knowledge, cost, and need as potential reasons for not using these modalities. Results show that controlling for predisposing, enabling, and need factors, recent immigrants use CAM less than the U.S.-born. Lack of knowledge of CAM modalities partially explains why some recent immigrants do not use acupuncture, chiropractic, or relaxation, while established immigrants cite lack of need as a reason for not using yoga. Cost does not explain immigrants’ lower use of these five modalities. Finally, ethnicity moderates the association between immigrant status and reasons for not using CAM.

Details

The Impact of Demographics on Health and Health Care: Race, Ethnicity and Other Social Factors
Type: Book
ISBN: 978-1-84950-715-8

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Book part
Publication date: 9 August 2012

Christopher J. Fries

Research is needed that uses large enough samples to facilitate disaggregation of users by specific types of complementary/alternative medical (CAM) practices and by…

Abstract

Research is needed that uses large enough samples to facilitate disaggregation of users by specific types of complementary/alternative medical (CAM) practices and by ethnicity in order to examine possible patterns in the use of CAM therapies not accorded efficacy by family physicians. The objective of this study is too use data from a large population health survey to determine the relationship ethnicity, measured with multiple indicators, has with the use of CAM therapies classified as “accepted” or “rejected” by family physicians in terms of efficacy. Using data from the Canadian Community Health Survey (CCHS) Cycle 1.1, logistic regression models estimate the factors influencing the use of the two binary categories of CAM therapy. Measures of ethnicity available in the CCHS are used to focus on ethnic origin, comparing North American and Foreign born, and on ethnic identification, comparing Whites with Asians, South Asians, Blacks, Latin Americans, Aboriginals, and others. Whites and North American born had higher odds of using “accepted” therapies, whereas immigrant visible minorities and those with Asian ethnic identities were more likely to use “rejected” therapies. This research confirms that ethnicity constitutes a cultural resource upon which users of CAM draw as they make their health-care decisions, sometimes despite the recommendations of family physicians.

Details

Issues in Health and Health Care Related to Race/Ethnicity, Immigration, SES and Gender
Type: Book
ISBN: 978-1-78190-125-0

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Book part
Publication date: 29 July 2009

Jennie Jacobs Kronenfeld and Stephanie L. Ayers

Complementary and alternative medicine (CAM) as a topic of research and as an approach within the health care delivery system has become increasingly accepted. Aided by…

Abstract

Complementary and alternative medicine (CAM) as a topic of research and as an approach within the health care delivery system has become increasingly accepted. Aided by the holistic movement, and after a century and a half of striving for legitimacy, CAM is also increasingly becoming more accepted by mainstream medicine. This chapter reviews the social sources of disparities in use of CAM, with a greater focus on English-speaking countries, and especially the US. This chapter will briefly highlight the basic underlying principles of CAM as linked to its history and discuss types of CAM. The major focus of this chapter will be a review of the literature on social factors and use of CAM, looking at such factors as age, gender, socioeconomic status, race/ethnicity and immigration status, and health status. As part of this, we will also discuss the integration of CAM and conventional care. In conclusion, future directions for social science research in CAM will be discussed, specifically elaborating on the importance of the social sciences linking CAM with other growing interests in health and wellness.

Details

Social Sources of Disparities in Health and Health Care and Linkages to Policy, Population Concerns and Providers of Care
Type: Book
ISBN: 978-1-84855-835-9

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Article
Publication date: 28 December 2020

Weibin Lan, Shouwen Fan and Shuai Fan

This paper aims to propose an elementary approach toward the identification of assembly defects of a cam curved groove mechanism.

Abstract

Purpose

This paper aims to propose an elementary approach toward the identification of assembly defects of a cam curved groove mechanism.

Design/methodology/approach

A numerical analysis method for identifying the assembly defects of the cam curved groove mechanism is proposed by resorting to Hertz contact theory. A general mathematical model is established to analyze the kinematic and dynamic characteristics with an interference fit between the main roller and cam curved groove, including the contact points of the external and internal ring.

Findings

The analysis method of the contact point characteristics of the cam curved groove mechanism is given in this paper, and the kinematic and dynamic characteristics of the main roller can be analyzed. The numerical examples presented in this paper are implemented in MATLAB, feasibility and validity of the above algorithm are verified by the finite element method.

Originality/value

Regarding the defects of the interference fit, the findings of this paper can serve as a reference for researchers in reducing the defects in the design process of the cam mechanism.

Details

Assembly Automation, vol. 41 no. 1
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 1 May 2001

Fawzy Soliman, Stewart Clegg and Tarek Tantoush

Current advances in information technology and, in particular, computer‐aided design/computer‐aided manufacturing (CAD/CAM) and enterprise resources planning (ERP…

Abstract

Current advances in information technology and, in particular, computer‐aided design/computer‐aided manufacturing (CAD/CAM) and enterprise resources planning (ERP) systems, have led organisations to undertake significant investments in these systems. Next generation manufacturers require both systems to maintain or gain a competitive advantage, reduce risks and improve productivity and viability. In addition, recent attention to the implementation of CAD/CAM systems highlights their important role in automating complex design and next generation manufacturing processes. In the next millennium more manufacturers are likely to implement CAD/CAM and ERP systems and hence issues in the integration of CAD/CAM with ERP systems must become a major concern. Accordingly, this paper will: explore the problems of integration of CAD/CAM systems with ERP systems; study how the severity of these problems relates to CAD/CAM integration success; propose a set of critical success factors (CSF) for the integration of CAD/CAM with ERP systems; suggest hypotheses to study the relevance of these CSF for successful integration of CAD/CAM with ERP systems. In addition, the paper also demonstrates the importance of successful integration of CAD/CAM systems with other applications for next generation manufacturers. These findings suggest that integration of CAD/CAM systems with ERP systems is complex, involving many factors.

Details

International Journal of Operations & Production Management, vol. 21 no. 5/6
Type: Research Article
ISSN: 0144-3577

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Article
Publication date: 1 February 2013

Adedeji O. Esan, Mohammed K. Khan, Hong S. Qi and Craig Naylor

Cost reduction through the use of technology has become the competitive strength of companies. The benefits of technology integration are quite credible and have been…

Abstract

Purpose

Cost reduction through the use of technology has become the competitive strength of companies. The benefits of technology integration are quite credible and have been effective in business competition. The purpose of this paper is to describe an integrated manufacturing strategy for the deployment of a CAD/CAM system in a small, medium manufacturing enterprise (SMME).

Design/methodology/approach

A case study of a SMME is utilised in deploying an integrated CAD/CAM system for practical application of manufacturing technology for achieving sustainable growth through lean systems design (LSD). The paper presents a techno‐economic and technology change management framework, with an application of a holistic set of lean deployment tools that include establishing a strategic and operational plan for implementing CAD/CAM systems as a means to achieving world‐class performance.

Findings

The paper shows that the CAD/CAM integration within the case company increased knowledge of CAD/CAM technology, productivity, and flexibility whilst reducing throughput times. Based on the literature review and the current case study, a framework for ideal CAD/CAM implementation has been proposed. The paper also shows that management and organisational structures are key inhibitors for successful implementation of technology integration.

Research limitations/implications

The paper uses a single case study to validate deployment of the integrated manufacturing strategy in SMMEs. Hence there is a limitation to its generality.

Practical implications

The paper provides an opportunity to further understand CAD/CAM system implementation protocols within a well structured framework and its configuration within SMMEs.

Social implications

The CAD/CAM implementation framework will allow the SMMEs to achieve Lean manufacturing (thereby minimising wastes) leading to improved growth and employment rates.

Originality/value

The presentation of conceptualisation, development and implementation of an integrated CAD/CAM system in support of organisational wide Lean manufacturing initiative in SMMEs is an originality of this paper.

Details

Journal of Manufacturing Technology Management, vol. 24 no. 2
Type: Research Article
ISSN: 1741-038X

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Article
Publication date: 8 June 2010

S. Vinodh, G. Sundararaj, S.R. Devadasan, D. Kuttalingam and D. Rajanayagam

The purpose of this paper is to report a research which is carried out to examine the possibility of applying finite element analysis (FEA) and computer‐aided…

Abstract

Purpose

The purpose of this paper is to report a research which is carried out to examine the possibility of applying finite element analysis (FEA) and computer‐aided design/computer‐aided manufacturing (CAD/CAM) concepts in a typical organisational environment to acquire the characteristics of agile manufacturing (AM).

Design/methodology/approach

One of the components of a model of electronic switch manufactured by a company was chosen as the candidate of this research. Five new models of this component incorporated with agile characteristics were developed in electronic environment using Moldflow Plastics Insight software.

Findings

The experiences of conducting this research being reported in this paper indicate the possibility of adopting FEA‐integrated CAD/CAM concept for achieving agility. However, certain hindrances have to be overcome to pursue deeper journey by the contemporary organisations in this direction.

Research limitations/implications

This research is conducted on one component of a product manufactured by a company. The typical scenario prevailing in the company is similar that is seen in many companies situated in other parts of the worlds. Hence, the contributions of this research, particularly the roadmap would be useful for adopting FEA and CAD/CAM concepts to achieve agility in contemporary organisations.

Practical implications

The research reported in this paper has shown the way of focusing FEA‐integrated CAD/CAM utilities towards enhancing AM capabilities of contemporary organisations.

Originality/value

The literature survey conducted in the beginning of this research indicated that deeper research in the direction of applying FEA‐integrated CAD/CAM concept for acquiring agile characteristics is yet to start. Hence, the research reported in this paper is original and valuable.

Details

Journal of Manufacturing Technology Management, vol. 21 no. 5
Type: Research Article
ISSN: 1741-038X

Keywords

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