Patent ID: 7507045

Claim:
A low paper sensor mechanism for a printer comprising: two paper supports, the first paper support supportive of a paper supply roll when the printer is mounted to a substantially horizontal surface and the second paper support supportive of the paper supply roll when the printer is mounted to a substantially vertical surface, each paper support including: a fixed roller rotatable about a fixed roller axis; a movable roller rotatable about a movable roller axis and pivotable about the fixed roller axis from a start position to an end position, the movable roller and fixed roller spaced a predetermined distance apart and capable of supporting a paper supply roll; and a biasing member in operable communication with the movable roller and capable of biasing the movable roller toward the end position; and a detection device including: a sensor having an emitting element and a detecting element, the emitting element being disposed in a line of sight of the detecting element; a paddle assembly having two paddles, one paddle extending beneath each paper support from a central bar and a trip arm extending from the central bar; and a paddle biasing member disposed to bias the trip arm to disrupt the line of sight; wherein the movable roller is translatable from the start position toward the end position as a diameter of the paper supply roll decreases to less than or equal to the predetermined distance thereby allowing the paper supply roll to fall between the fixed roller and the movable roller thus exerting a force on one paddle of the two paddles causing the paddle assembly to rotate about a bar axis thereby restoring the line of sight.