Two-speed clutch and retro-fit kit

A clutch apparatus comprising:

• a rotatable input member;
• a spring housing rotatably fixed to the input member;
• a cover rotatably mounted relative to the input and axially moveable relative to the input, wherein at least a portion of the cover comprises a material capable of conducting eddy currents;
• a first magnet holder removably attached to the spring housing and rotatably fixed thereto, the first magnet holder defining a first radial retention groove;
• a first permanent magnet carried by the first radial retention groove in the magnet holder, wherein the first radial retention groove restricts movement of the first permanent magnet in a radial direction while providing a magnet access passage in another direction through which the first permanent magnet can pass, and wherein the first permanent magnet is positioned in an opposing relationship relative to the material of the cover capable of conducting eddy currents;
• and
• an adhesive securing the first permanent magnet within the first radial retention groove of the first magnet holder for limiting movement through the magnet access passage,
• wherein axial movement of the cover selectively engages and disengages a frictional torque coupling between cover and the input member, and
• wherein in a frictionally disengaged axial position the cover is configured to rotate with the input by way of an eddy current coupling at a speed different from that provided by the frictional torque coupling.

A two-speed retro-fit kit for use with an on/off friction clutch that includes a rotatable input member, an existing spring housing rotatably fixed to the input member, a spring for biasing the spring housing, and an existing cover rotatably mounted relative to the input and axially moveable relative to the input, the kit comprising:

• a replacement spring housing for replacing the existing spring housing of the clutch, wherein the replacement spring housing includes a plurality of insets circumferentially spaced from one another;
• a plurality of magnet holder assemblies each comprising:
• a body portion;
• a first radial retention groove defined in the body portion;
• a second radial retention groove defined in the body portion adjacent to the first radial retention groove;
• a flange extending from the body portion, wherein the flange has a connection feature for securing the first magnet holder to the replacement spring housing at the first inset;
• a first permanent magnet engaged with the first radial retention groove in the body portion;
• and
• a second permanent magnet engaged with the second radial retention groove in the body portion, wherein magnetic orientations of the first permanent magnet and the second permanent magnet are arranged to be opposite one another;
• and
• a replacement cover with a least a portion comprising a material that conducts eddy currents positioned near the first and second permanent magnets to transmit torque between the spring housing and the cover through an eddy current rotational engagement whenever the clutch is frictionally disengaged.

A method for converting an on/off clutch to a two-speed clutch, the method comprising:

• removing an existing output member;
• removing an existing spring housing;
• attaching a new spring housing having an inset to an existing input member;
• attaching a first magnet holder to the new spring housing, wherein the first magnet holder carries a first permanent magnet;
• and
• installing a new output member so as to be rotatable and axially moveable relative to the new spring housing, wherein the new output member includes a first portion positioned adjacent to the first permanent magnet, and wherein the first portion of the output member comprises the material capable of conducting eddy currents.