Remove the cone-shaped top from the lamp, which most likely includes the metal grate covering the halogen lamp.

My lamp has 3 "indents" (red circle) that slide into paths on the cone (red square). To remove the cone, twist the cone in the clockwise direction (while viewing from the shaft side of the lamp).

Chances are, if you have the problem that this lamp had, the cone will already be loose or not connected to the lamp. The cone is what presses down on the safety switch.