Dana Corporation

Warner Electric Brake & Clutch Company

Other

Robert A Olsen

Dwight E Booth

Paul A Larson

David C Gustin

Paul P Newton

An electromagnetically actuated friction clutch includes a rotatably driven input gear. A rotatable armature is connected to the input gear and includes a friction face and nitrocarburized outer surfaces. A pole piece has a pole face for engaging the friction face of the armature and nitrocarburized outer surfaces. An electromagnet generates an electromagnetic field to shift the armature from a disengaged position to an engaged position wherein the friction face of the armature and the pole face of the pole piece are frictionally engaged. An output shaft is driven by the input gear when the armature is in the engaged position. The nitrocarburized outer surfaces of the armature and the pole piece resist wear, while interior portions of the armature and pole piece direct magnetic flux flow along a desired path.

Nitrocarburized component for an electromagnetic friction clutch assembly

A soft start electromagnetic coupling has a driven member and a driving member that are coupled together in response to a magnetic flux produced by a direct current flow through a winding on the clutch. When the members are coupled by an electromagnetic flux, they may slip relative to reach other during starting, when the load on the coupling changes or when the accessory driven by the coupling freezes or becomes jammed. Relative slippage of the members produces an alternating current component in the direct current flow that is detected to indicate the slippage. The presence of an alternating current component can be sensed through a rectifier or frequency filter. Preferably, the presence of a persistent alternating current component causes a switch to open, interrupting the flow of direct current to the coupling. Interruption of the current flow disengages the coupling and prevents damage to other accessories that may be driven by the same endless belt and to the belt that engages the driven member of the coupling.

Apparatus and method for sensing clutch slippage

The rotor and armature of an electromagnetic clutch are formed with multiple regions of high magnetic reluctance defined by slots which are shaped and located such that the radial relation between the slots of the rotor and the slots of the armature changes as one member rotates relative to the other. As a result, the flux density across the air gap between the rotor and the armature varies when the armature slips relative to the rotor during initial engagement of the two. This lowers the average torque transmitted by the rotor to the armature and allows the clutch to engage gradually or with a soft-start before building up to full torque.

Soft-start electromagnetic coupling

The field shell of an electromagnet is formed with angularly spaced flanges which define a magnetic pole and which also serve as a mounting hub for a coil assembly consisting of a bobbin and a multiple turn winding. Resilient fingers on the bobbin snap into openings in the flanges to hold the bobbin and the shell in assembled relationship. Tabs are located between and project inwardly from the flanges and are used to mount the shell in a fixed position.

Field assembly for an electromagnet

The magnet core of an electromagnetic clutch is substantially J-shaped in radial cross-section and includes an outer pole ring which is spaced radially outwardly from and which only partially surrounds the outer pole ring of the rotor of the clutch. The controlled transfer of flux between the core and the rotor occurs both in a radial direction and in an axial direction.

Electromagnetic coupling

A method and apparatus for testing the integrity of spot welds made by a welding machine without destroying the manufactured parts being produced, said method and apparatus including welding together a pair of angle members made from the same sheet material as the parts being manufactured to form a 'T-shaped' test specimen with the outwardly extending cross arm of this 'T' forming attachment portions and providing a testing tool constructed and arranged to pull apart the welded together portions of the angles and test the integrity of the weld with a minimum of force being applied thereto.

Growing community of inventors

Janesville, WI, United States of America

Robert A Olsen