[ Papers ]

Journal of the Korean Society of Manufacturing Technology Engineers - Vol. 28, No. 5, pp.274-279

ISSN: 2508-5107 (Online)

Print publication date 15 Oct 2019

Received 21 Aug 2019 Accepted 11 Sep 2019

DOI: https://doi.org/10.7735/ksmte.2019.28.5.274

가스 차단기용 투입 캠의 표면피로수명

권순만^a^{, *}

Surface Fatigue Life of Close Cam for Gas Circuit Breaker

Soon-man Kwon^a^{, *}

aSchool of Mechanical Engineering, Changwon National University, 20, Changwondaehak-ro, Uichang-gu, Changwon, Gyeongnam-do, 51140, Korea

Correspondence to: ^*Tel.: +82-55-213-3629 Fax: +82-55-263-5221 E-mail address: smkwon@changwon.ac.kr (Soon-man Kwon).

Abstract

The contact surface fatigue life of the close cam of a spring operating mechanism for a gas circuit breaker was considered in this paper. Firstly, the design method for a disk cam with an oscillating roller follower was presented with the introduction of the instant center and homogeneous coordinate transformation. Then, the contact stress was investigated according to the shape factor of the cam displacement function. The increase in shape factor confirmed that the contact fatigue life was increased by lowering the contact stress, but the required closing time into the gas interrupter could not be met. Attention was focused on the rocker arm ratio (RAR) to satisfy both the contact fatigue life and closing time. We found that by changing the RAR without changing the shape factor, the contact fatigue life increased significantly without changing the closing speed.

Keywords:

Gas circuit breaker, Close cam, Oscillating roller follower, Rocker arm ratio, Contact stress

References

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