| 摘要 |
PURPOSE:To make the torque transfer capacity of an automobile fan coupling variable in accordance with the temperature of engine cooling water, by using a variable capacity unit for controlling the effective storage capacity of liquid in a liquid chamber of a housing. CONSTITUTION:When the temperature of air passing through a radiator is low, a movable dam element 35 is at a position as shown in the figure, the effective capacity of chambers 13a, 13b being relatively expanded. At this moment, viscous fluid such as silicon oil in a coupling housing 7 is maldistributed, due to the centrifugal force caused bu revolution of the housing 7, along the external circumference of a liquid chamber 13. Accordingly no viscous fluid exists substantially in labyrinth passages 23, 25, revolution is not transferred to a rotor 21 and a cooling fan 20 is not turned, while the element 35 is displaced through a shaft 33 by means of an action of a bimetal 34 caused by a rise in air temperature, and the effective capacity of chambers 13a, 13b are reduced. Then the fan 20 gets started turning slowly. |
