Semiconductor wafer cassette positioning and detection mechanism
AssigneePRI Automation, Inc.
InventorsKenneth J. Bazydola, Robert L. Price
Life of this patent
Estimating the term…
Abstract
An apparatus for detecting the presence of a wafer cassette, or pod, resting on an arrangement of pins allows cassette detection without interfering with insertion of a robotic paddle arm beneath the cassette to remove it for transport. A cassette resides on an arrangement of beveled pins which mate with corresponding receptacles on the underside. Pins supporting the cassette have a spring biased, hollow outer cylinder coaxially mounted around a center post. A cassette placed on the pins displaces the outer cylinder downward a sufficient distance to trigger a sensor. Upon removal of the cassette, the outer cylinder is displaced upwards, resetting the sensor.
Claims10
A semiconductor wafer cassette positioning and detecting apparatus comprising:
- a cassette support surface having at least three pin assemblies disposed therein to receive a wafer cassette, at least one of said pin assemblies comprising:
- an cylinder having a center bore;
- a center post having an upper end and a lower end, the lower end fixed to the support surface, the post slidably disposed in said center bore;
- a biasing member disposed to bias said cylinder toward the upper end of said center post;
- and
- a sensor disposed to detect a predetermined point of travel of said outer cylinder toward said lower end of said center post.
An apparatus for detecting an object resting on a pin nest arrangement comprising:
- a support surface;
- a pin assembly comprising:
- a center post having an upper end and a lower end, the lower end fixed to the support surface;
- an outer cylinder having a center bore coaxially mounted for sliding movement on the center post;
- a biasing member disposed to bias said outer cylinder toward the upper end of said center post;
- a sensor located to detect a predetermined point of travel of said outer cylinder toward said lower end of said center post.
Dependencies are inferred from the claim text.