Slim profile digital tachometer including planar block and rotor having spokes and clamp

A magneto-resistive tachometer comprising:

• a) an enclosure formed as a substantially planar block having front and back sides and a peripheral edge defining a substantially uniform thickness of the block of about 3/4", and formed with a central through opening therein, and a plurality of bolt holes sized and located for alignment with bolt holes on a standard NEMA C-type monitor end face;
• said block having a recess formed therein adjacent said central through opening and adapted to receive a sensor electronics package, and a radial slot in the block between said central through opening and said recess for receiving a sensing element;
• and
• b) a first selected drum having a peripheral surface with encoded sensor patterns thereon adapted to be sensed by said sensing element, said drum having a center hub connected to said peripheral surface by a plurality of spokes, said center hub adapted for clamping engagement with an output shaft of the motor within said center Opening of said enclosure and in radially adjacent position relative to said sensing element, at least one of said spokes provided with an integral clamp for securing said drum to the output shaft of the motor, said integral clamp comprising a slot in at least one of said spokes, and a clamping screw passing transversely through said slot.

A tachometer comprising:

• a) a one piece enclosure formed as a substantially planar block having front and back sides and a peripheral edge defining a substantially uniform thickness of the block, and formed with a central through opening therein, and a plurality of bolt holes sized and located for alignment with bolt holes on a standard NEMA C-type motor end face;
• said block having a recess formed adjacent said central through opening and adapted to receive a sensor electronics package, and a radial slot in said block between said central through opening and said recess for receiving a sensing element;
• and
• b) a plurality of interchangeable sensor drums for selective use with said enclosure, each having a peripheral surface with encoded sensor patterns thereon adapted to be sensed by said sensing element such that each drum provides a different number of pulses per revolution;
• each drum having a center hub connected to said peripheral surface by a plurality of radial spokes and means on at least one of said spokes for locking said hub to an output shaft of a motor.

A tachometer comprising:

• a) an enclosure formed as a substantially planar block having front and back sides and a peripheral edge defining a substantially uniform thickness of the block, and formed with a central through opening therein, and a plurality of bolt holes sized and located for alignment with bolt holes on a standard NEMA C-type motor end face;
• said block having a recess formed therein adjacent said central through opening and adapted to receive a sensor electronics package, and a radial slot between said central through opening and said recess for receiving a sensing element;
• and
• b) a plurality of interchangeable sensor drums for selective use with said enclosure, each having a center hub and peripheral surface with encoded sensor patterns thereon adapted to be sensed by said sensing element such that each drum provides a different number of pulses per revolution;
• wherein said center hub is connected to said peripheral surface by at least two radial spokes, and wherein locking means are provided on at least one of said spokes for locking said hub to an output shaft of a motor, said locking means comprising a slot in at least one of said spokes, and a clamping screw passing transversely through said slot.

A tachometer comprising:

• a) an enclosure formed as a substantially planar block having front and back sides and a peripheral edge defining a substantially uniform thickness of the block, and formed with a central through opening therein, and a plurality of bolt holes sized and located for alignment with bolt holes on a standard NEMA C-type motor end face;
• said block having a recess formed therein adjacent said central through opening and adapted to receive a sensor electronics package, and a radial slot between said central through opening and said recess for receiving a sensing element;
• and
• b) a plurality of interchangeable sensor drums for selective use with said enclosure, each having a center hub and peripheral surface with encoded sensor patterns thereon adapted to be sensed by said sensing element such that each drum provides a different number of pulses per revolution;
• wherein said center hub is connected to said peripheral surface by at least three radial spokes, and wherein locking means are provided on at least one of said spokes for locking said hub to an output shaft of a motor, said locking means comprising a slot in at least one of said spokes, and a clamping screw passing transversely through said slot.