摘要:
A viscous fluid type heat generator which includes a housing assembly defining a heat generating chamber and a heat receiving chamber arranged adjacent to the heat generating chamber via a partition wall disposed therebetween. A rotor element is mounted to be rotated by a drive shaft for rotation within the heat generating chamber. A viscous fluid is held in a gap defined between the inner wall surfaces of the heat generating chamber and the outer faces of the rotor element, for heat generation under shearing stress applied by the rotation of the rotor element. A heat exchanging fluid circulates through the heat receiving chamber to receive heat transferred through the partition wall from the heat generating chamber. A plurality of grooves, protuberances or expression are formed on at least one of the inner wall surfaces of the heat generating chamber to increase the total heat transfer surface area in the inner wall surfaces, and thus enhance a heat transfer efficiency through the partition wall. The density of arrangement of the grooves in the outer peripheral area of the inner wall surface is larger than that in the inner peripheral area of the inner wall surface.
摘要:
A screw engagement portion between a pulley and a shaft is provided with a thread in a direction to increase the tightening torque when the pulley is driven. A breakable part broken by the axial tension produced when the tightening torque acting on the screw engagement portion is above a predetermined value, is also provided. The stress to break the breakable part is mainly a tensile stress. The tensile stress is substantially uniformly distributed in a cross section and, hence, the stress distribution of the breakable part can be relatively precisely predicted and analyzed. Consequently, the necessity of determining aspects of the breakable part, such as dimension, material, and the like, by trial and error is reduced. The breakable part can be broken without being subject to fatigue fracture.