Magnetically positioned coding device

Claim 2

A code tab arrangement comprising a carrier having a plurality of spaced apart C-shaped channels, a plurality of tabs supported in said channels, each of the center portions of said C-shaped channels connecting its arms being magnetized at predetermined locations along its length, the front face of said portions being of one polarity and its back face of the other polarity, the polarity at each of said predetermined locations being alternated in series, said tabs being magnetized to have polarity patterns such that said tabs are magnetically attracted to remain in alternate ones of said series of locations but are magnetically repelled from the other alternate ones of said series of locations, said tabs being provided with a protuberance at each edge where it would contact the open arms of said channel, said tabs being caused to pivot about said protuberances in the vicinity of the undesired ones of said predetermined locations thereby modifying the magnetic circuit comprising said tabs and channel region and causing said tabs to snap into desired ones of said predetermined locations.

Claim 3

A coding device for identifying objects moving relative to a sensing station, said coding device comprising a carrier, said carrier comprising at least one channel, at least one tab slideable along said channel of said carrier, said tab comprising a magnetic material and being magnetized such that the front face is of one polarity and the back face is of the opposite polarity, said front face of said tab carrying a retroreflective surface for reflecting incident light toward said sensing station, said channel comprising a magnetic region extending the length of the channel, said magnetic region being magnetized at predetermined locations along the length of the channel, the front and back faces of said region being of opposite polarity at said predetermined locations and the polarity of said predetermined locations alternating in series along said length at predetermined spacings such that said tab is repelled from undesired ones of said predetermined locations and attracted to desired ones of said predetermined locations, said channel being dimensioned to permit the back face of said tab to slide along said magnetic region thereof in the vicinity of the attraction location and to permit the front face of said tab to slide along the edge of the two open arms of said channel in the vicinity of the repelling location, said tab being provided with a protuberance where its center line contacts the edge of the two open arms of said channel, said tab being caused to pivot about said protuberances in the vicinity of the undesired ones of said predetermined locations thereby modifying the magnetic circuit comprising said tab and channel region and causing said tab to snap into desired ones of said predetermined locations.

Claim 4

A coding device for identifying objects moving relative to a sensing station, said coding device comprising a carrier, said carrier comprising at least one channel, at least one tab slideable along said channel of said carrier, said tab comprising a magnetic material and being magnetized such that the front face is of one polarity and the back face is of the opposite polarity, said front face of said tab carrying a retroreflective surface for reflecting incident light toward said sensing station, said channel comprising a magnetic region extending the length of the channel, said magnetic region being magnetized at predetermined locations along the length of the channel, the front and back faces of said region being of opposite polarity at said predetermined locations and the polarity of said predetermined locations alternating in series along said length at predetermined spacings such that said tab is repelled from undesired ones of said predetermined locations and attracted to desired ones of said predetermined locations, said channel being dimensioned to permit the back face of said tab to slide along said magnetic region thereof in the vicinity of the attraction location and to permit the front face of said tab to slide along the edge of the two open arms of said channel in the vicinity of the repelling location, said tab being provided with a protuberance where its center line contacts the edge of the two open arms of said channel, said tab being caused to pivot about said protuberances in the vicinity of the undesired ones of said predetermined locations thereby modifying the magnetic circuit comprising said tab and channel region and causing said tab to snap into desired ones of said predetermined locations.

Claim 5

A coding device for identifying objects moving relative to a sensing station, said coding device comprising a carrier, said carrier comprising a plurality of parallel open faceD channels, a plurality of tabs slideable along the channels of said carrier, each of said tabs comprising a magnetic material and being magnetized such that the front faces are of the same one polarity and all of the back faces are of the same opposite polarity, said front faces of said tabs each carrying a retroreflective surface for reflecting incident light toward said sensing station, each of said channels comprising a magnetic region extending the length of the channel, said magnetic region being magnetized at predetermined locations along the length of the channel, the front and back faces of said region being of opposite polarity at said predetermined locations and the polarity of said predetermined locations alternating in series along said length at predetermined spacings such that said tabs are repelled from undesired ones of said predetermined locations and attracted to desired ones of said predetermined locations, said tabs further including protuberances along the edges of their front faces for slideably contacting the channels along the edges of their open faces, said protuberances being located to cause said tab to pivot thereabout as the tab moves into an undesired location.

Claim 6

A coding device for identifying objects moving relative to a sensing station, said coding device comprising a carrier, said carrier comprising a plurality of parallel open faceD channels, a plurality of tabs slideable along the channels of said carrier, each of said tabs comprising a magnetic material and being magnetized such that the front faces are of the same one polarity and all of the back faces are of the same opposite polarity, said front faces of said tabs each carrying a retroreflective surface for reflecting incident light toward said sensing station, each of said channels comprising a magnetic region extending the length of the channel, said magnetic region being magnetized at predetermined locations along the length of the channel, the front and back faces of said region being of opposite polarity at said predetermined locations and the polarity of said predetermined locations alternating in series along said length at predetermined spacings such that said tabs are repelled from undesired ones of said predetermined locations and attracted to desired ones of said predetermined locations, said tabs further including protuberances along the edges of their front faces for slideably contacting the channels along the edges of their open faces, said protuberances being located to cause said tab to pivot thereabout as the tab moves into an undesired location.