Patent ID: 7105765

Claim:
An orbital welder comprising: a body defining a tube passage; a weld tip; a rotor coupled to said weld tip for causing said weld tip to rotate about an axis; a light source fixed to said body and disposed to emit light toward said tube passage such that said emitted light will at least partially impinge upon a tube placed in said tube passage; a detector fixed to said body and disposed to detect said light emitted by said light source from said tube passage; and an indicator; and wherein the intensity of said detected light depends on the position of said tube; said detector is disposed to detect light reflected by said tube placed in said tube passage; and said indicator is operative to indicate when the intensity of said detected light is below a first predetermined intensity indicative that a minimum amount of said emitted light is impinging upon said tube, when the intensity of said detected light is above a second predetermined intensity indicative that a maximum amount of said emitted light is impinging upon said tube, and when the intensity of said detected light has reached a third predetermined intensity indicative of alignment of a mating end of said tube with said weld tip, said third predetermined intensity being greater than said first predetermined intensity and less than said second predetermined intensity.