Patent ID: 6998863

Claim:
A test head for a semiconductor integrated circuit tester, the test head comprising: a housing including guide elements for positioning a plurality of pin electronics cards in the housing, a backplane structure attached to the housing in a manner permitting pivotal movement of the backplane structure relative to the housing about an axis of pivotal movement between an open position, in which the backplane structure affords access to the interior of the housing, and a closed position, the backplane structure having a proximal edge and a distal edge, wherein the proximal edge of the backplane structure is closer than the distal edge to the axis of pivotal movement, and a latch mechanism for forcing the backplane structure towards the closed position from an engagement position that is between the open position and the closed position, wherein the latch mechanism comprises: a cam follower that projects from the backplane structure at the distal edge thereof in a direction substantially perpendicular to the axis of pivotal movement of the backplane structure, a cam member that is attached to the housing and is moveable relative to the housing, the cam member being formed with a cam slot including an entrance region for receiving the cam follower as the backplane structure approaches the engagement position and also including a working region, and a drive mechanism effective to drive the cam plate to move relative to the housing, the cam slot being configured such that in the event that the cam follower is located in the working region of the cam slot, movement of the cam member in one direction urges the backplane structure towards the closed position and movement in the opposite direction urges the backplane structure towards the engagement position.