Abstract: A method and apparatus are used to balance an open blade fan of the kind used with trucks, diesel engine driven generator sets, and the like. An apparatus is used to spin the fans and a vibration sensor senses vibrations and a light beam is used to indicate the location to attach a balancing weight. The fan is spun again and the vibrations measured and additional weights are attached at different specified locations until the measured vibrations are below a predetermined level. The fan includes a plastic body with integral, plastic fan blades which is attached to a central metal hub plate with configured weights attached to matching configured portions of the plastic body. The preferred weights are clips with barbs that pierce the plastic body. The metal hub plates are electrostatically painted to provide a uniformly thick coating with good adhesion.

Abstract: A magnetic fan clutch having a magnetic field coupling which uses a light weight, strong plastic driving member and driven member to rotate fan blades which are also made of plastic. The fan clutch also uses a plastic mounting member for attaching to a vehicle. Plastic may be used for a vehicle or truck fan clutch because the magnetic coupling between the series of coils on the driving member and the magnetic elements on the driven member may be modulated to provide a slower torque transfer from zero to a full torque transfer over a longer controlled period of time such as over six seconds to eliminate the relatively sharp impact torque transfer pulse heretofore found in fan clutches. This slower and modulated torque transfer with slippage between the driving member and driven member during the torque transfer period reduces the fast acceleration and the resistant high inertia and torque loads of conventional fan clutches as typically found in vehicles or other heavy duty applications.

Abstract: An electromagnetic coupler couples a first rotating element with a second element with a torque transfer between the first and second elements. The coupling is solely by a magnetic field which can be fully coupled, fully uncoupled or modulated to provide a variable transmission of power between the first and second elements. The electromagnetic coupler comprises a set radially disposed electromagnets and a concentric set of pole pieces separated by an air gap. The magnetic field between the electromagnets and the pole pieces is increased as the current through the electromagnets is increased. At low current, there is substantial slippage between the respective driving and driven elements. With full magnetic coupling, the electromagnets and pole pieces are fully coupled or without any slippage therebetween. When the magnetic field is eliminated, there is no torque transfer between the driving and driven elements.

Abstract: A drive for the compressor of a vehicle air conditioner has a magnetic clutch for mechanically driving the compressor shaft within a predetermined range of torque and a rotatable input element on the magnetic clutch to be rotated by the vehicle motor at varying speeds with changes in the vehicle motor's speed. The drive includes a first electromagnetic element on the rotatable input element and a compressor shaft on the output side of the magnetic clutch for supplying torque to drive the compressor. Also, there is a second electromagnetic element on the compressor shaft with a magnetic field between the first and second electromagnetic elements to rotate the compressor. An electric control is provided for varying the electrical power to the electromagnetic clutch as the vehicle motor changes speed to vary the magnetic field and torque being applied to rotate the compressor shaft.

Abstract: A magnetic slip clutch system that can be used tin a number of different applications where a slip clutch is desired to be used; and particularly, to applications where the clutch is desired to be fully disengaged, i.e., free-wheeling, fully engaged to transmit 100% of the power, or coupled in a modulated or slip manner for transmission of a variable amount of power. The torque transfer is modulated by controlling the electric power to the clutch.

Abstract: A new and improved fan clutch system for use with an internal combustion engine which provides variable speed drive of the fan by the engine with the coupling between the fan and the engine being solely by a magnetic field. The variable speed drive provides true proportional control of the convective heat transfer from the radiator.