The present invention relates to a magnetic tape cassette comprising upper and lower halves of cassette forming the cassette body wherein supply and take-up reels for a tape are to be loaded, a front cover that swivels and covers rotatably the front side of the cassette where the tape runs and a front cover spring that keeps causing the front cover to be swiveled in one direction. In the upper half of cassette offered by the invention, the side wall of the upper half of cassette is provided with a loading opening, and when a shaft provided on the front cover for supporting the front cover when it swivels or rotates is positioned at the corner of the loading opening, it is possible to mount the front cover regularly and finally only on the upper half of cassette owing to a stopper protrusion that checks the downward movement of the shaft provided on the front cover and a slip-prevention protrusion that checks the forward movement of the same shaft.

A magnetic tape cassette, particularly a video tape cassette which is provided with a hinged front panel prestressed by a tension spring, the coil of which is positioned on an axle on the inside of the side wall of the front panel. The free end of the long spring leg grips beneath the front of an upper housing half of the cassette, which constrains the long spring leg. A lower housing half has a hinged locking plate on the inside, in the area of the front panel. The locking plate has a obliquely extending projection projecting over the plate, which projection being eccentric to the center of rotation of the plate has a surface off set from the axis of rotation of said hinged locking plate, and on the surface of oblique projection the long spring leg stressed between the upper housing half and the projection of the plate to produce a moment of force on the plate tending to swing the plate on the axis of rotation.

In a video tape cassette having upper and define a substantially rectangular housing with an opening extending along a side thereof between end walls of the housing for containing reels having tape wound thereon and guided between the reels in a run extending across the opening, and a lid structure which is pivotally mounted on the housing for movement by a coil spring from an open position exposing the tape run to a closed position in which the lid structure covers the tape run; the assembling of the tape cassette is facilitated by providing anchors on the lid structure by which the coil spring is initially or tentatively located during the mounting of the lid structure on one the housing portions, whereupon the coil spring is transferred into engagement with an anchor on that one housing portion in preparation for assembling of the latter with the other housing portion. An improved coil spring has a leg portion which defines an area of contact with a latch element which is greater than that defined by the length of the leg portion, such as by binding the end of the leg portion.

A tape cassette with a pivotal lid having a tape wound on reels inside a cassette made up of upper and lower shells and light holes in the sides of the cassette for detecting the ends of the tape using light beams is made easy to assemble by dustproofing ribs for preventing dust and the like from entering through the light holes each being split into two dustproofing rib parts, one of these parts being provided on the pivotal lid and the other being provided on the lower shell. The dustproofing rib parts are so disposed that with the pivotal lid in an open position the upper shell can be assembled to the lower shell easily in one straight-line movement without its direction being changed. Facing surfaces of the two dustproofing rib parts constituting each dustproofing rib are sloping or stepped to effectively prevent dust from passing between the dustproofing rib parts.