Experimental Ball Bearing Impedance Analysis Under Different Speed and Electrical Conditions

Abstract

This is a repository copy of Experimental ball bearing impedance analysis under different speed and electrical conditions.

Electrical Impedance Spectroscopy for Precise Film Thickness Assessment in Line Contacts

“…Each contact behaves more as sistance than a capacitance. Therefore, since 2010, the electric impedance has been ferred to determine the lubrication film thickness [36][37][38][39][40] in EHL as well as the oil breakdown occurring in mixed and boundary lubrication [40,41]. The measured im Instead of relying on previous correlation, Wilson [26] and later, Cen and Lugt [27] addressed this challenge by generating a calibration curve for a specific load.…”

“…Each contact behaves more as a resistance than a capacitance. Therefore, since 2010, the electric impedance has been preferred to determine the lubrication film thickness [36][37][38][39][40] in EHL as well as the oil-film breakdown occurring in mixed and boundary lubrication [40,41]. The measured impedance consists of an ohmic (or resistive) contribution R and a capacitive contribution C. The ohmic contribution becomes important in cases of direct metallic contact, whereas capacitance is dominant in cases of full-film lubrication.…”

Analysis of the Electrical Impedance of Graphite and Silver Graphite Carbon Brushes for Use in the Impedance Measurement of Sensory Utilizable Machine Elements

“…The impedance of the gear mesh, which is directly dependent on the lubrication condition and the proportion of mixed friction [9,10], is to be used to derive conclusions regarding rotational speed, acting torque, and potentially surface damage. Another example are sensory utilizable rolling element bearings that have been subject to research activities for many years-e.g., [11][12][13][14][15]-and are currently being brought to production maturity in the industry; e.g., [16]. As shown in Figure 1, the electrical capacitance of a rolling element bearing is measured-e.g., by a suitable impedance measurement of Z DUT -and used for sensory purposes on the basis of the relationship between lubrication film thickness and capacitance.…”

“…At the moment, sliding contacts are often used for test rigs and applications of SuME on rotating systems; e.g., [6][7][8][12][13][14][15]. These are specialized elements, such as carbon or steel brushes, which are pressed onto the rotating element by means of-e.g., a preloaded spring.…”

“…Although sliding contacts are described extensively in the literature-e.g., [17,18]-and used in both research and industrial practice, there is still no comprehensive understanding of their influence on impedance measurements in the context of SuME. Despite initial studies of the electrical behavior of sliding contacts in this context [19,20], random sliding contacts are often selected for test setups without having systematically chosen a suitable solution; e.g., [6][7][8][12][13][14][15]. Thus, sliding contacts in applications differ by the material used, the relative contact position to the rotating element, and other parameters.…”