April 26, 2004
Gamma Design Nearing Completion
Following last week's design review, changes have been incorporated in the model to address items developed in the review. Major changes include elimination of the sliding lens cover and hinges, improvements in the optical path, provision of a "crash cage", and improved sealing.
Following a design review on 21 April 04, the Gamma prototype design has been altered in the following respects:
The extruded heatsink has been revised to receive in a slot the front plate, which now has no hinges. This permits elimination of 4 screws. The heat flow path has been improved by moving a screw slot outside the path. Two additional screw slots have been added, and they have been enlarged to permit use of a self-threading steel insert.
The front plate (projection lens plate) has been converted to a cut-off piece of flat aluminum stock, eliminating the need for a special extrusion. In the process, the sliding lens cover and the hinges have been eliminated. The area in contact with the cover gaskets has been increased.
The cover plates have lost their hinge halves, and additional screw holes have been added for fastening.
A felt sealing washer has been added to the film advance knob assembly.
A third condenser lens has been added and the optical path lengthened by allowing the projection lens to protrude from the front plate. This allows use of a dipped vinyl lens cap in lieu of the sliding door.
The film gate has been revised to accommodate the changed projection lens position.
A pair of deformable guard rings (made from 2mm stamped soft aluminum sheet) have been added to protect the protruding lens and the body of the projector from damage in the event of a fall. The rings will absorb the fall energy by deformation, and can be bent back close to original position, or replaced. The new screw attachment of the covers makes this addition possible.
Posted by Allen Armstrong at April 26, 2004 08:53 AM
