Drive system for automatic meter reader

Claim 2

A remotely reading meter register comprising optical encoder means for producing a remotely readable electrical output signal indicative of the rotational positions of a plurality of coupled meter register indicator shafts, said optical encoder means comprising a light source mounted at least partially within a reflector member shaped to project collimated light, and a rotatable apertured scanning disc Operable selectively to transmit the collimated light to a photosensor means in the form of a train of read-out light pulses which are converted by said photosensor means into said electrical output signal, and a scanning disc drive system comprising a hollow core hysteresis motor which includes an annular stator closely surrounding said reflector member and scanning disc and driving a rotor provided by a portion of said scanning disc.

Claim 3

A meter register according to claim 1 wherein said scanning disc is cupped and provided with a cylindrical rim comprising a continuous band of cobalt alloy ferromagnetic material.

Claim 4

A meter register according to claim 2 wherein said stator comprises a single concentrated excitation winding and a pair of annular stator lamination and shading ring assemblies, each of said stator lamination and shading ring assemblies having at least one unshaded and shaded salient stator pole arranged in a ring surrounding said cylindrical rim so as to provide in combination an approximately constant rotating magnetic field.

Claim 5

A meter register according to claim 3 wherein each of said stator lamination and shading ring assemblies includes an unshaded pole lamination, a shading ring, and a shaded pole lamination, each of said laminations having at least one orthogonally bent finger providing said salient stator poles.

Claim 6

A remote reading meter register comprising optical encoder means for producing a remotely readable electrical output signal indicative of the rotational positions of a plurality of coupled meter register indicator shafts, said optical encoder means comprising a light source and associated conically shaped reflector member for projecting collimated light, a rotatable cupped scanning disc mounted coaxially with said reflector member, a plurality of encoding discs each secured for rotation with one of said indicator shafts, and a collecting optics and photosensor assembly, said scanning disc being operable selectively to transmit the collimated light through aligned apertures at least in said scanning and encoding discs in the form of a train of read-out light pulses which are incident on said collecting optics and photosensor assembly and converted to said electrical output signal, and a scanning disc drive system comprising an unsymmetrical, hollow core, shaded pole, synchronous hysteresis motor which includes an annular stator closely surrounding said reflector member and cupped scanning disc, said scanning disc having a cylindrical rim comprising a continuous band of cobalt alloy ferromagnetic material for providing a rotor driven by said stator.

Claim 7

A remote reading meter register comprising optical encoder means for producing a remotely readable electrical output signal indicative of the rotational positions of a plurality of coupled meter register indicator shafts, said optical encoder means comprising a light source and associated conically shaped reflector member for projecting collimated light, a rotatable cupped scanning disc mounted coaxially with said reflector member, a plurality of encoding discs each secured for rotation with one of said indicator shafts, and a collecting optics and photosensor assembly, said scanning disc being operable selectively to transmit the collimated light through aligned apertures at least in said scanning and encoding discs in the form of a train of read-out light pulses which are incident on said collecting optics and photosensor assembly and converted to said electrical output signal, and a scanning disc drive system comprising an unsymmetrical, hollow core, shaded pole, synchronous hysteresis motor which includes an annular stator closely surrounding said reflector member and cupped scanning disc, said scanning disc having a cylindrical rim comprising a continuous band of cobalt alloy ferromagnetic material for providing a rotor driven by said stator.

Claim 8

A meter register according to claim 5 wherein said stator comprises a single concentrated excitation winding between a pair of stator lamination and shading ring assemblies, each of said stator lamination and shading ring assemblies having at least one unshaded and shaded salient stator pole arranged in a ring about said cylindrical rim and in combination generating an approximately constant rotating magnetic field.

Claim 9

A meter register according to claim 6 wherein each of said stator lamination and shading ring assemblies includes an unshaded pole lamination, a shading ring, and a shaded pole lamination, said laminations each having a plurality of orthogonally bent fingers of different lengths that are interleaved to provide said salient stator poles.

Claim 10

A meter register according to claim 7 wherein one of said shaded pole laminations has an integral curved hollow core member for receiving said stator laminations, shading rings, and excitation winding in stacked relation, and mounting said stator about said reflector member.