Pub Date : 1900-01-01DOI: 10.1109/HOLM.1991.170804
S. Kharin
A mathematical model describing interdependent transient temperature and electromagnetic fields in electrical contacts at three stages of pre-arcing of opening of contact (closed, initial opening, and bridging) is discussed. The dynamics of temperature change and its dependence on the contact films, and Thomson, Kohler, and Peltier effects are described. It is shown that nonuniform current density in the contact spot over the frequency range of 0-10 Hz is enhanced by current constriction rather than by the skin-effect. The relationships between the rate of appearance of the extra forces in contacts during the opening period are established. The model of thermal explosion is invoked to explain the mechanism of spontaneous separation of contact resulting from the combined action of electrodynamic and thermal forces generated by the explosive evaporation of material at high current. The model was used to describe the bridging stage of contact opening. It is established that the shape of the bridge, its temperature field, and the lifetime mechanism of rupture are determined by the dynamics of contact opening and also forces resulting from the surface tension, the pinch effect, and Joule, Thomson, and tunnel heating.<>
{"title":"Transient thermophysical phenomena at the pre-arcing period during opening of electrical contacts","authors":"S. Kharin","doi":"10.1109/HOLM.1991.170804","DOIUrl":"https://doi.org/10.1109/HOLM.1991.170804","url":null,"abstract":"A mathematical model describing interdependent transient temperature and electromagnetic fields in electrical contacts at three stages of pre-arcing of opening of contact (closed, initial opening, and bridging) is discussed. The dynamics of temperature change and its dependence on the contact films, and Thomson, Kohler, and Peltier effects are described. It is shown that nonuniform current density in the contact spot over the frequency range of 0-10 Hz is enhanced by current constriction rather than by the skin-effect. The relationships between the rate of appearance of the extra forces in contacts during the opening period are established. The model of thermal explosion is invoked to explain the mechanism of spontaneous separation of contact resulting from the combined action of electrodynamic and thermal forces generated by the explosive evaporation of material at high current. The model was used to describe the bridging stage of contact opening. It is established that the shape of the bridge, its temperature field, and the lifetime mechanism of rupture are determined by the dynamics of contact opening and also forces resulting from the surface tension, the pinch effect, and Joule, Thomson, and tunnel heating.<<ETX>>","PeriodicalId":368900,"journal":{"name":"Electrical Contacts - 1991 Proceedings of the Thirty-Seventh IEEE HOLM Conference on Electrical Contacts","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129886057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The miniaturization limit of the reed switch with respect to the magnetic and mechanical properties is discussed assuming that the contact rating, the switching current and voltage, the carry current, and the breakdown voltage are 1 VA, 0.1 A, 24 V, 0.3 A, and 150 V, respectively. Assuming that the contact rating, the switching current and voltage, the carry current, and the breakdown voltage decrease, it was found that the ultraminiature reed switch with glass inner diameter of 1.0 mm and glass inner length of 4.0 mm can be put in mass production by using the existing process technology. This reed switch has a contact force of 1 gf and is suitable in the field of microelectronics.<>
{"title":"Magnetic and mechanical design of ultraminiature Reed switches","authors":"T. Kobayashi, K. Hinohara, C. Kawakita","doi":"10.1109/33.142891","DOIUrl":"https://doi.org/10.1109/33.142891","url":null,"abstract":"The miniaturization limit of the reed switch with respect to the magnetic and mechanical properties is discussed assuming that the contact rating, the switching current and voltage, the carry current, and the breakdown voltage are 1 VA, 0.1 A, 24 V, 0.3 A, and 150 V, respectively. Assuming that the contact rating, the switching current and voltage, the carry current, and the breakdown voltage decrease, it was found that the ultraminiature reed switch with glass inner diameter of 1.0 mm and glass inner length of 4.0 mm can be put in mass production by using the existing process technology. This reed switch has a contact force of 1 gf and is suitable in the field of microelectronics.<<ETX>>","PeriodicalId":368900,"journal":{"name":"Electrical Contacts - 1991 Proceedings of the Thirty-Seventh IEEE HOLM Conference on Electrical Contacts","volume":"7 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123805495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1109/HOLM.1991.170833
J. Aronstein
Failures of aluminum connections in various residential electrical applications are examined. Specific examples are provided, including aluminum bus bar contacts, aluminum-bodied connectors, and aluminum-shell lamp sockets. Design factors of the failed connections are discussed in terms of criteria for successful long-lived contact to aluminum. Deficiencies of the designs and the applicable qualification standards are discussed.<>
{"title":"Failure of aluminum connections in residential applications","authors":"J. Aronstein","doi":"10.1109/HOLM.1991.170833","DOIUrl":"https://doi.org/10.1109/HOLM.1991.170833","url":null,"abstract":"Failures of aluminum connections in various residential electrical applications are examined. Specific examples are provided, including aluminum bus bar contacts, aluminum-bodied connectors, and aluminum-shell lamp sockets. Design factors of the failed connections are discussed in terms of criteria for successful long-lived contact to aluminum. Deficiencies of the designs and the applicable qualification standards are discussed.<<ETX>>","PeriodicalId":368900,"journal":{"name":"Electrical Contacts - 1991 Proceedings of the Thirty-Seventh IEEE HOLM Conference on Electrical Contacts","volume":"116 37","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131912991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1109/HOLM.1991.170827
J. Chao, R. Gore
The results of a process to better understand the IBM GIT gaseous corrosion test are presented. Previous work over the past two years has centered around the changing of a single gas of a mixture and analyzing the subsequent corrosion products. In the work reported in the paper, an effort to achieve a particular corrosion outcome by changing multiple gas concentrations is attempted by applying knowledge gained from these previous experiments. The possible synergistic effects between different gas species were considered in a qualitative manner to determine the gas concentrations to be used for generating the desired composition of corrosion products. Results from these exposures were analyzed using coulometric reduction, SEM/EDX (scanning electron microscopy/energy-dispersive X-ray spectroscopy), and X-ray diffraction.<>
{"title":"Evaluation of a mixed flowing gas test","authors":"J. Chao, R. Gore","doi":"10.1109/HOLM.1991.170827","DOIUrl":"https://doi.org/10.1109/HOLM.1991.170827","url":null,"abstract":"The results of a process to better understand the IBM GIT gaseous corrosion test are presented. Previous work over the past two years has centered around the changing of a single gas of a mixture and analyzing the subsequent corrosion products. In the work reported in the paper, an effort to achieve a particular corrosion outcome by changing multiple gas concentrations is attempted by applying knowledge gained from these previous experiments. The possible synergistic effects between different gas species were considered in a qualitative manner to determine the gas concentrations to be used for generating the desired composition of corrosion products. Results from these exposures were analyzed using coulometric reduction, SEM/EDX (scanning electron microscopy/energy-dispersive X-ray spectroscopy), and X-ray diffraction.<<ETX>>","PeriodicalId":368900,"journal":{"name":"Electrical Contacts - 1991 Proceedings of the Thirty-Seventh IEEE HOLM Conference on Electrical Contacts","volume":"53 16","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113942138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1900-01-01DOI: 10.1109/HOLM.1991.170799
D. Kuhlmann-wilsdorf
The broadly based use of theory for understanding, and hence improving, electrical contacts is considered. The author discusses such uses in four areas: (i) studies of monolithic metal-graphite brushes for determining their operating limits; (ii) development of high-performance metal fiber brushes based on theoretical considerations; (iii) developing a computer program for calculating contact spot temperatures, being the principal determinant of top brush performance; and (iv) studies of microscopic processes at a-spots including adsorbed layers, with the aim of optimizing the operating conditions of sliding contacts.<>
{"title":"Uses of theory in the design of sliding electrical contacts","authors":"D. Kuhlmann-wilsdorf","doi":"10.1109/HOLM.1991.170799","DOIUrl":"https://doi.org/10.1109/HOLM.1991.170799","url":null,"abstract":"The broadly based use of theory for understanding, and hence improving, electrical contacts is considered. The author discusses such uses in four areas: (i) studies of monolithic metal-graphite brushes for determining their operating limits; (ii) development of high-performance metal fiber brushes based on theoretical considerations; (iii) developing a computer program for calculating contact spot temperatures, being the principal determinant of top brush performance; and (iv) studies of microscopic processes at a-spots including adsorbed layers, with the aim of optimizing the operating conditions of sliding contacts.<<ETX>>","PeriodicalId":368900,"journal":{"name":"Electrical Contacts - 1991 Proceedings of the Thirty-Seventh IEEE HOLM Conference on Electrical Contacts","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126320720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：