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A Form-Closed Cam-Follower Mechanism for a Breath Simulator Machine

  • R. F. OliveiraEmail author
  • P. Flores
  • S. F. Teixeira
  • H. M. C. Marques
  • J. C. Teixeira
Conference paper
Part of the Mechanisms and Machine Science book series (Mechan. Machine Science, volume 24)

Abstract

The worldwide incidence of asthma yields 250,000 deaths annually, being almost all of these deaths avoidable. The inhalation therapy is the preferable route to deliver bronchodilator/anti-inflammatory drugs to the patient lungs. Within this route of treatment, pressurized Metered Dose Inhalers (pMDI’s) are the cornerstone devices. When coupled with a Valved Holding Chamber (VHC), its efficiency increases and the limitations almost vanish. The VHC devices efficiency is something of interest to measure. For that, it is necessary an experimental setup that evaluates the amount of drug delivered by the device. This setup shall replicate a human breath waveform as input, therefore a breath simulator machine was build. The report herein describes the project process of the form-closed cam-follower mechanism necessary to replicate the waveform. The design and dimensional constrains are input in the cam design, leading to a piston diameter of 63.0 mm and a cam base diameter of 250.0 mm. A performance analysis to the pressure angle, curvature radius and backlash impact force, is reported. It can be concluded that a larger diameter would improve the performance results substantially.

Keywords

Form-closed Cam-follower mechanism Breath simulator Synthesis 

Notes

Acknowledgments

The first author would like to express his gratitude to the Portuguese Foundation for Science and Technology (FCT) through the PhD grant SFRH/BD/76458/2011. This work was financed by National Funds-Portuguese Foundation for Science and Technology, under Strategic Project PEst-C/EME/UI4077/2011 and PEst-OE/EME/UI0252/2011.

The authors are also grateful for the help of Dr. Eurico Seabra from the University of Minho with the data acquisition from the LVDT.

References

  1. 1.
    CAN/CSA-Z264.1-02(R2008) (2008) Spacers and holding chambers for use with metered-dose inhalers. Canadian Standards Association, TorentoGoogle Scholar
  2. 2.
    Flores P (2009) Projecto de mecanismos Came-Seguidor. Publindústria, PortoGoogle Scholar
  3. 3.
    Foss SA, Keppel JW (1999) In vitro testing of MDI spacers: a technique for measuring respirable dose output with actuation in-phase or out-of-phase with inhalation. Respir Care 44(12):1474–1485Google Scholar
  4. 4.
    Global Initiative for Asthma (2012) Global strategy for asthma management and prevention. Technical report, GINA. http://www.ginasthma.org
  5. 5.
    Masoli M, Fabian D, Holt S, Beasley R (2004) The global burden of asthma: executive summary of the GINA Dissemination Committee report. Allergy 59(5):469–478CrossRefGoogle Scholar
  6. 6.
    Mitchell JP, Dolovich MB (2012) Clinically relevant test methods to establish in vitro equivalence for spacers and valved holding chambers used with pressurized metered dose inhalers (pMDIs). J Aerosol Med Pulm Drug Deliv 25(4):217–242CrossRefGoogle Scholar
  7. 7.
    Mitchell JP, Nagel MW (2004) Particle Size Analysis of Aerosols from Medicinal Inhalers. KONA Powder Part J 22:32–65CrossRefGoogle Scholar
  8. 8.
    National Heart Lung and Blood Institute (2007) Expert Panel Report 3: guidelines for the diagnosis and management of asthma. Technical report, National Heart Lung and Blood Institute (NHLBI), BethesdaGoogle Scholar
  9. 9.
    Norton RL (2002) Cam design and manufacturing handbook. Industrial Press, New YorkGoogle Scholar
  10. 10.
    Oliveira RF, Teixeira JC, Marques HMC, Teixeira SFCF (2013) An experimental setup for API assessment of a valved holding chamber device. In: Proceedings ASME 2013 international mechanical engineering congress and exposition—IMECE2013, p 8. ASME, San DiegoGoogle Scholar
  11. 11.
    Scottish Intercollegiate Guidelines Network, British Thoracic Society (2011) British guideline on the management of asthma: a national clinical guideline. Technical report, BTS and SIGN, UKGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • R. F. Oliveira
    • 1
    Email author
  • P. Flores
    • 1
  • S. F. Teixeira
    • 2
  • H. M. C. Marques
    • 3
  • J. C. Teixeira
    • 1
  1. 1.CT2M R&D CenterUniversity of MinhoBragaPortugal
  2. 2.CGIT R&D CenterUniversity of MinhoBragaPortugal
  3. 3.iMed.UL R&D CenterUniversity of LisbonLisbonPortugal

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