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Article
Publication date: 18 November 2013

Haitian Zou, Baolin Wang, Fumin Song and Lianyu Fu

The purpose of this paper is to verify the feasibility and reliability of mineral casting applied in high-precision printed circuit board (PCB) drilling machine. The mechanical…

Abstract

Purpose

The purpose of this paper is to verify the feasibility and reliability of mineral casting applied in high-precision printed circuit board (PCB) drilling machine. The mechanical properties of machine frame are quantified to provide a solution for machine tool industry to seek a perfect substance competing with classic materials such as cast iron and granite.

Design/methodology/approach

The optimal design of machine frame is performed via the CAD system combined with finite element analysis (FEA). The mechanical properties of the frame elements are evaluated by a series of mechanical experiments: static performance is quantified by flatness tests, dynamic behavior is estimated by experimental and numerical models, respectively. Meanwhile, the performance of the frame element with traditional materials is examined experimentally.

Findings

Mineral casting parts can be successfully applied to PCB drilling machine to meet high accuracy requirements. The characteristic of mineral casing gives the most possibilities in structural design. The frame parts show good static/dynamic behaviors by structural optimization processes. Especially, the machine frame with mineral casting gains a great weight reduction compared with traditional materials.

Originality/value

The application of mineral casting in PCB drilling machine offers greater design flexibility and innovative system solutions. The combination of FEA is convincing to achieve optimal structure and ideal weight to maximize the economic and technical benefits. Moreover, lightweight design of machine structural components achieves not only higher kinematic/dynamic precision but also considerable cost reduction.

Details

Circuit World, vol. 39 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 8 February 2011

Hongyan Shi, Fumin Song and Lianyu Fu

The purpose of this paper is to present a system for accurately measuring drilling force in the printed circuit board micro drilling process and to characterize the drilling force…

Abstract

Purpose

The purpose of this paper is to present a system for accurately measuring drilling force in the printed circuit board micro drilling process and to characterize the drilling force to provide a better understanding of the micro drilling process.

Design/methodology/approach

The drilling force measurement system was established first. Then the drilling force in printed circuit board micro drilling process was characterized experimentally. In particular, the drilling forces in drilling halogen‐free and lead‐free assembly compatible printed circuit boards and the drilling force characteristics in ultra small hole drilling were investigated.

Findings

A drilling force measurement system, with the key component of a KISTLER 9256C2 dynamometer, can accurately measure the drilling forces in the printed circuit board micro drilling process. The micro drilling process can be characterized by drilling force. Meanwhile, drilling force is very sensitive to drill breakage and drilling force can be utilized to detect drill breakage in the micro drilling process.

Originality/value

The paper presents a system for accurately measuring the drilling force. Drilling force provides fundamental information for the optimal design of micro drill bits. Drilling force can also characterize the micro drilling process, especially the ultra small hole micro drilling process.

Details

Circuit World, vol. 37 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 17 May 2011

Fumin Song, Lianyu Fu and Fei Zhang

The purpose of this paper is to present and describe a solution of aluminum substrate drilling.

Abstract

Purpose

The purpose of this paper is to present and describe a solution of aluminum substrate drilling.

Design/methodology/approach

The development of LED and printed circuit board with metal substrate are reviewed first. Then the challenges of drilling metal substrate, particularly the aluminum substrate, are described. To find the solution, coated micro drill bit with optimized helix angle is developed. The performance of developed micro drill bit is examined via drilling force investigation. Finally, the drilling tests are conducted to verify the solution of aluminum substrate drilling.

Findings

Coated drill bit is a very good choice to solve the problems of drilling burr and chip clogging in aluminum substrate drilling. The reason is that the drilling force can be obviously reduced by using a coated drill bit. The drill bit with medium helix angle is beneficial to prevent chip clogging. A satisfactory solution of aluminum substrate drilling can be achieved by applying coated drill bit with medium helix angle together with appropriate entry board.

Originality/value

The paper presents a satisfactory solution of aluminum substrate drilling. By employing the presented solution, the problems of drilling burr and chip clogging can be avoided in aluminum substrate drilling.

Details

Circuit World, vol. 37 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 February 2013

Chuji Chen, Hongyan Shi and Fumin Song

The purpose of this paper is to present a method for evaluating the structural dynamic characteristics of a flying probe tester.

Abstract

Purpose

The purpose of this paper is to present a method for evaluating the structural dynamic characteristics of a flying probe tester.

Design/methodology/approach

The dynamic characteristics of a flying probe tester framework were analyzed based on a finite element analysis method. First, modal analysis was carried out to characterize the modal parameters of the structure. Second, the harmonic response was analyzed according to the modal analysis and the response curve of the structural system was studied. Finally, transient analysis was conducted to obtain the transient response of the structures at the beginning of the vibration.

Findings

The natural frequency and the response frequency of a natural granite structure was the highest and the transient vibration displacement amplitude was the smallest compared with cast iron and artificial stone structures.

Originality/value

A comprehensive understanding of the dynamic characteristics of the framework of a flying probe tester with three different materials has been achieved. The results of the analyses provide a reference for the framework design of a flying probe tester.

Content available
Article
Publication date: 18 November 2013

Martin Goosey

211

Abstract

Details

Circuit World, vol. 39 no. 4
Type: Research Article
ISSN: 0305-6120

Book part
Publication date: 8 August 2017

Anna Zakharzhevskaya

This paper examines diverging views on the Chongqing model, the policy experiment led by Bo Xilai from 2007 to 2012 that was famous for its “red songs” and the campaign against…

Abstract

This paper examines diverging views on the Chongqing model, the policy experiment led by Bo Xilai from 2007 to 2012 that was famous for its “red songs” and the campaign against organized crime. It has impressed both the supporters of socialist identity of China and the supporters of liberal identity and led to an intense debate concerning China’s path of development. This paper attempts to discuss and clarify to what extent the Chongqing model represented a genuine socialist experiment and the implications of the model for China’s future.

Details

Return of Marxian Macro-Dynamics in East Asia
Type: Book
ISBN: 978-1-78714-477-4

Keywords

Open Access
Article
Publication date: 6 January 2022

Meng Ye, Fumin Deng, Li Yang and Xuedong Liang

This paper aims to build a scientific evaluation index system for regional low-carbon circular economic development. Taking Sichuan Province as the empirical research object, the…

1739

Abstract

Purpose

This paper aims to build a scientific evaluation index system for regional low-carbon circular economic development. Taking Sichuan Province as the empirical research object, the paper evaluates its low-carbon circular economy (LCCE) development level and proposes policy recommendations for climate change improvement based on the evaluation results.

Design/methodology/approach

This paper, first, built an evaluation index system with 30 indicators within six subsystems, namely, economic development, social progress, energy consumption, low-carbon emissions, carbon sink capacity and environmental carrying capacity. Second, develop an “entropy weight-grey correlation” evaluation method. Finally, from a practical point of view, measure the development level of LCCE in Sichuan Province, China, from 2008 to 2018.

Findings

It was found that Sichuan LCCE development had a general downward trend from 2008 to 2012 and a steady upward trend from 2012 to 2018; however, the overall level was low. The main factors affecting the LCCE development are lagging energy consumption and environmental carrying capacity subsystem developments.

Research limitations/implications

This paper puts forward relevant suggestions for improving the development of a low-carbon economy and climate change for the reference of policymakers.

Originality/value

This paper built an evaluation index system with 30 indicators for regional low carbon circular economic development. The evaluation method of “entropy weight-grey correlation” is used to measure the development level of regional LCCE in Sichuan Province, China.

Details

International Journal of Climate Change Strategies and Management, vol. 14 no. 1
Type: Research Article
ISSN: 1756-8692

Keywords

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