Pinion 4 and handle 5, rigidly attached together, rotate about fixed axis A. Indexing plunger 1 slides along axis B and has integral gear rack b meshing with pinion 4. Disk 2 is locked in its indexed positions when plunger 1 enters a hole a of the disk due to the action of spring 3. Plunger 1 is withdrawn from hole a to release disk 2 by turning pinion 4 with handle 5.
$2397$SG,I$