On Characteristics of Hydraulic Torque Converter under Special Operating Conditions

Abstract

This paper deals with first the complete characteristics of P-T-S type normal torque converter including its characteristics under special operating conditions other than the normal power transmitting direction or the range of operating speed ratio, and secodly the effect of air bubble mixed intentionally into the working oil on the characteristics. For experiments, a single-stage normal torque converter with three members was provided. (1) All special operating conditions can be classified into eight cases as given in Table 1. In the vicinity of transition point from a case to the other, discontinuity of characteristics is observed. Excepting this phenomenon, observed characteristics can be deduced qualitatively from the theoretical calculation. (2) So far as she air-content in oil does not exceed a certain limit, the normal characteristics are maintained almost as they are. Increasing the air-content more than the limit, characteristics decrease intensely, particularly in torque, to those of fluid coupling or the like. This limit of content is observed, independently of charging pressure at about 3% decrease of specific weight of air-oil mixture measured at minimum pressure zone in the converter circuit.