Locking of car radios and the like

Claim 1

Means for lockingly fixing of apparatus onto a fixed part by engaging a fixed screw threaded member secured to and projecting from the apparatus after passing the threaded member through a complementary hole in the fixed part comprising a circular nut threaded on the screw threaded member having depressions therein opening inwardly, a washer on the screw threaded member resiliently biased between said nut and the fixed part, and a trim plate between said washer and the fixed part, fixable to the fixed part and having a hole for the screw threaded member of the apparatus and circular cavities adjacent said hole forming shoulder formations, said washer including leaf spring-like tongues having a horseshoe shaped spacing and clearance between unattached edges of said leaf spring-like tongues and the material of said washer, forming the free end of said tongues and projecting from said washer into said depressions of said nut in a direction to lockingly engage said nut against rotation in a direction for loosening whiLe permitting rotation of said nut in a direction for tightening, holding elements in the form of hook shaped projections extending from the opposed face of said washer at positions spaced from the inner and outer edges of said washer and having laterally extending terminal portions projecting into said cavities of said trim plate and underlying said shoulder formations to lockingly engage said washer in said trim plate to combine with said nut to prevent rotation in a direction for loosening while permitting rotation of said nut in a direction for tightening, said terminal portions extending in an opposite direction of rotation than the free end of said tongues.