Folding arm for overhead projector

DETAILED DESCRIPTION The foregoing objective is achieved in a portable overhead projector having a folding arm.
The arm is pivotally connected to the base, and is part of a four-bar linkage which includes the housing of the projector head.
To collapse the unit, a handle on the arm is pushed; the arm folds down toward the base, and the four-bar linkage, including the arm, simultaneously rotates the projector head 180.
degree.
.
The projector head and arm are then laid flush against the base, reducing the overall height of the unit for transportation and storage.
During this operation, a pulley system inside the projector head automatically closes the mirror which is pivotally attached to the projector head.
When the projector is to be set up, the same handle is simply pulled upward; the arm is raised to an upright position, the projector head rotates to its operational state, and the mirror on the head flips up.