Carrier positional displacement detecting mechanism

Abstract

In a horizontal conveyance type auto-handler, the operation of a carrier is stopped when a positional displacement of the carrier relative to a test board is detected. A shaft is provided on a center of a guide pin on the test board. When the carrier which is displaced relative to the test board is lowered, the shaft is pushed down by the carrier, and the lowering of the shaft is detected by an optical sensor, thereby stopping the lowering operation of the carrier.

What is claimed is:  
     
         1 . A carrier positional displacement detecting mechanism provided in an auto-handler comprising a carrier for mounting an IC thereon, and a measuring part for measuring the IC mounted on the carrier, said carrier having a positioning hole, and a measuring part having a projection wherein the projection is inserted into the positioning hole so as to position the carrier relative to the measuring part, said carrier positional displacement detecting mechanism comprising: 
 positional displacement time contact means projected from and disposed on each tip end of the projection and capable of passing through the positioning hole only when the projection and the positioning hole correspond to each other; and    contact detection means for detecting the contact between the positional displacement time contact means and the carrier and outputting a carrier positional displacement signal.    
     
     
         2 . The carrier positional displacement detecting mechanism according to  claim 1 , wherein the positional displacement time contact means is a shaft projected from and biased by the projection and the contact detection means is a sensor for detecting a rear end of the shaft.  
     
     
         3 . The carrier positional displacement detecting mechanism according to  claim 1 , wherein the positioning operation of the carrier is stopped when the contact detection means detects the carrier positional displacement signal.