Automotive vehicles, especially sport utility vehicles, pick-up trucks and vans, required periodic service of the viscous fan clutch assembly or water pump. The viscous fan clutch assembly is coupled to a threaded shaft of a water pump with a threaded coupling. This shaft is freewheeling, and must be controlled to prevent its rotation when connecting or disconnecting the shaft to the viscous fan clutch assembly. The common method of removing the viscous fan clutch assembly is to hold the water pump fully stationary with a holding wrench. Such holding wrenches are relatively thin in order to fit into a constricted space between the water pump pulley and the fan clutch assembly. Then, using an open ended turning wrench engaging the threaded coupling on the viscous fan clutch assembly, with an opposite turning motion, the viscous fan clutch assembly is unthreaded from the water pump threaded shaft. With this method, the viscous fan clutch assembly may be removed and replaced, and thereafter the water pump may also be removed and replaced.
Some water pump pulleys are held to the water pump by a number of fasteners (i.e. bolts and nut assemblies). These bolts or nuts are usually in a group of four, five, or even more, and extend from the surface of the water pump pulley. The bolts or nuts are accessed and held by the holding wrench after which the turning wrench is used to remove or replace the viscous fan clutch assembly. Other pulleys are pressed onto the water pump and are each formed with a number of recesses, the walls of which are engaged by protrusions on the holding wrench to hold the pulley in place before the turning wrench is employed to remove or replace the viscous fan clutch assembly. Certain pulleys have outer surfaces with other configurations, such as raised flats and central nut designs, which need to be engaged to keep the pulley stationary before the turning wrench is applied.
Because of the variety in the shape and sizes of pulleys and because of the variation of the design, spacing and positioning of the fasteners, recesses and other engagement surfaces on these pulleys, it has been necessary to select the proper holding tool from a set of multiple holding tools when servicing water pumps and fan clutch assemblies. While some known holding tools and wrenches claim to be used with a wide variety of water pump pulleys, there remains a need to provide a single adjustable holding tool capable of universal application regardless of the size and the configuration of the pulleys.
USPTO Backgrounds
USPTO Backgrounds