Apparatus for hardware item inspection

Nut inspection apparatus for monitoring the presence of a bore hole in nuts and adaptable to also determine if threading is present on the inner surface thereof, comprising:

• a. a ramp for carrying said nuts, said ramp having a slot which defines an inspection position;
• b. means for generating a laser beam;
• c. means for splitting said laser beam into first and second beams;
• d. means for directing the first beam transverse the ramp and over the slot at the inspection position;
• e. a first photodetector for receiving said first beam in the absence of a nut at the inspection position;
• f. enable means responsive to the output of said first photodetector for generating an enable signal when a nut is at the inspection position;
• g. means for directing said second beam toward the inner surface of a nut at the inspection position;
• h. a second photodetector for receiving through said slot the light reflected from said inner surface;
• i. means enabled by said enable signal and responsive to the output of said second photodetector for counting occurrences during which the output of said second photodetector exceeds a first predetermined threshold level;
• j. means for generating a first occurrence indication when the accumulated count during said enable signal is one;
• and
• k. means enabled by the output of said first photodetector for generating a thread indicative occurrence indication when the output of said second photodetector exceeds a predetermined threshold level.

Apparatus for automatically examining the surfaces of hardware items progressing along a track and for determining the threading frequency thereof, comprising:

• a. means for determining the presence of an item at a predetermined inspection position along the track;
• b. means for directing a beam of light toward the inspection position;
• c. means for scanning said beam transverse the direction in which threads are running on a surface of an item at the inspection position;
• d. a photodetector positioned to detect the light reflected from said surface of the item at the inspection position;
• e. counting means coupled to the output of said photodetector for counting pulses which exceed a predetermined threshold level during the presence of an item at the inspection position;
• and
• f. means for generating an occurrence indication as a function of the final count for each item.