Mounting arrangements for levy springs acting against tape reels in a cassette

Claim 1

In a tape cassette comprising supply and take-up reels having a tape wound thereon and extending between said reels, a cassette housing containing said reels and including upper and lower portions with said lower portion having means comparatively engageable with said reels for rotatably positioning the latter within said housing, metal leaf spring means having resilient arms engageable at free ends with said supply and take-up reels, respectively, for urging said reels toward said lower housing portion, and means for mounting said leaf spring means in respect to said upper housing portion including at least one hole in said leaf spring means remote from said free ends of the resilient arms and a thermoplastic pin depending from said upper housing portion through each said hole and being thereafter formed by heat and pressure into a head for retaining said leaf spring means thereon; the improvement of said leaf spring means including a mounting portion having parallel opposed surfaces with said hole extending therethrough, and with the one of said surfaces of the leaf spring means facing away from said upper housing portion having a surface portion adjacent said hole which is preformed to have fine convex and concave irregularities that extend along substantially cross-hatched lines so as to diverge, at least in part, from circles concentric with said hole and are engaged by said head formed by heat and pressure on the pin for providing the formed head with complementary fine concave and convex irregularities which similarly extend along cross-hatched lines and interlock with said concave and convex irregularities, respectively of said surface portion to securely hold said leaf spring means and preclude turning and wobbling about said pin.