Temperature-sensitive fluid type fan coupling apparatus

A temperature-sensitive fluid-type fan coupling apparatus having a rotational axis, a driving side component disposed generally at one end of the rotational axis and a driven side component disposed generally at the opposed axial end of said rotational axis, said driving side component comprising a directly rotationally driven tightly sealed housing comprising a housing body and a housing cover and defining an interior therebetween, the interior of said housing defining an inner peripheral surface, a shaft core opening extending generally axially into the housing cover from the portion thereof adjacent the driven side component;

• said driven side component comprising a generally axially aligned rotary member having one end rotatably mounted in the shaft core opening of the housing, said rotary member having a cooling fan attached to a portion thereof external to said housing, a following disc securely mounted on the rotary member and disposed in the interior of said housing, said following disc comprising a depression extending into an axial end thereof facing away from the shaft core opening, said following disc being disposed in spaced relationship to the housing such that a torque transmission gap exists between the following disc and the inner peripheral surface of said housing interior, an oil circulation route extending in a radial direction through the following disc and extending between the depression therein and a radially outward portion of the torque transmission gap;
• a partition plate secured to the following disc and substantially covering the depression therein such that said depression defines an oil reservoir, said partition plate separating said oil reservoir from a torque transmission chamber communicating with said torque transmission gap, the partition plate being provided with an oil flow adjusting hole for providing communication between the oil reservoir and the torque transmission chamber;
• a valve member mounted inside said oil reservoir adjacent the partition plate and being movable relative thereto to selectively open or close the oil flow adjusting hole therein;
• a temperature-sensitive member secured to a portion of the rotary member external of said housing, a portion of said temperature-sensitive member being movable relative to said rotary member in response to changes in ambient temperature external of said housing;
• actuation means operatively connecting the movable portion of said temperature-sensitive member and said valve member for moving said valve member in response to changes in temperature sensed by said temperature-sensitive member, whereby the temperature-sensitive member is spaced from said oil reservoir thereby minimizing transfer of heat from oil in the oil reservoir to said temperaturesensitive member.