Abstract: A magnetic tape cassette has an outer peripheral rib for partitioning a part of a bottom plate, said rib being formed near the head receiving portion of an upper half casing wherein the inside portion of said bottom plate defined by said outer peripheral rib is tapered to have the thickness of said outer peripheral rib at the connecting point of said bottom plate to said outer peripheral rib.

Abstract: A magnetic tape cassette has a guard panel pivotally supported in the front of the upper half casing to be opened and closed in which a guide groove is formed near a hole for receiving a pin of the guard panel to guide the pin into the hole.

Abstract: A pivotal-shaft receiving hole formed in a thin-walled one-piece molded product for receiving a pivotal-shaft of another molded product is formed by a boss formed in one piece with the thin wall of said molded product and the pivotal-shaft receiving hole having a length greater than that of said pivotal-shaft which is formed through said thin wall and said boss.

Abstract: A leader tape for magnetic recording tape, characterized in that a coating film, consisting of a polymeric binder, an inorganic powder having a Mohs' hardness of 5 or above in an amount of not more than 5% by weight on the basis of the binder weight, and an antistatic agent, is formed on a plastic base.

Abstract: A magnetic tape cassette comprising a magnetic tape and two reels for winding said magnetic tape in the casing assembly has a through hole for determining the clamping position formed in the position corresponding to one of reel driving ribs for one reel and another through hole formed in the position between the adjacent ribs for the other reel.

Abstract: A recess for positioning a magnetic tape cassette inserted in a deck is formed near a corner of a guard panel, a small projection is formed on at least one of an inner surface of the guard panel or a front surface of a casing near the side edge of the magnetic tape. A tape guide shaft is fixed inside of a casing so as to place the surface of the tape guide slightly behind the level of the front surface of the casing.

Abstract: A tapping boss formed in one piece with the upper half casing for joining the lower half casing of a magnetic tape cassette comprises a stem having a cross sectional area slightly larger than the diameter of a tapping screw to receive the screw and a plurality of ribs which project radially from the cylindrical surface of said stem and whose top portions provide contact shoulders for the boss supporter of a lower half casing.

Abstract: A tape cassette formed from a cassette body having sections thereof which are adapted to be contacted by a tape and which have a surface roughness within the range of about 3 to 15 microns. In the production of such a cassette, those sections of the case which are adapted to be contacted by the tape are honed to provide a surface roughness within the specified micron range.

Abstract: A magnetic tape cassette comprises a tape running plane for a magnetic tape provided in the front of the casing assembly consisting of an upper half casing and a lower half casing, said magnetic tape being held in wound form and being capable of running inside the casing assembly and a front cover mounted to the casing assembly so as to open and close at the front of the assembly, said front cover being actuated by spring action in the direction closing the front part of the casing assembly by positioning one end of a coil spring fitted to the pivot pin in a rectangular groove formed in an inner surface of the upper half casing, wherein a rib having a slanted surface which is lowered toward said groove is provided at the side of said groove.

Abstract: A tape pad for a tape cassette for continuously contacting a magnetic tape under pressure in a casing wherein the tape pad has a fitting hollow in which a supporting member non-rotatably mounted on the casing is inserted to support the tape pad.

Abstract: The tape cassette comprises a guide rib extending upward from a lower casing to form a supporting surface for the entire width of the magnetic tape and a guide rib extending downward from an upper casing along the rear surface of the guide rib of the lower casing to provide a support for the guide rib of the lower casing.

Abstract: A reel for a tape cassette comprises reinforcing ribs connected, in the radial direction, with an inner peripheral surface of a magnetic tape winding core which is coaxially placed to the rotary axis. The magnetic tape winding core is formed by an inner tubular wall which is connected with the reinforcing ribs and an outer cylindrical or tubular wall which is coaxially connected with the inner tubular wall with a gap.

Abstract: A tape cassette comprises an upper half casing and a lower half casing and male hollow cylindrical projections having a notch mounted on either of the upper half casing or the lower half casing and female hollow recesses mounted on the other half casing at the corresponding positions. The upper and lower half casings are superposed to fit the male hollow cylindrical projects into the corresponding female hollow recesses and are fixed together by screwing self-tap bolts from the female hollow recesses into the male hollow cylindrical projections having notches to fix the projections on the inner surfaces of the female hollow recesses.

Abstract: A tape cassette including an upper half-case and a lower half-case and a tape guide wherein the tape guide is held only on one half-case and the upper and lower half-cases are fixed by screws only from one side of the half-cases through communicating holes except for a hole for the tape guide and wherein one end of a plate spring mounted on the one half-case and the other end or middle part of the plate spring is press-contacted with a lock plate to form a cover locking mechanism.

Abstract: A tape cassette braking mechanism which includes a resilient plate having a flat part and two bent parts wherein the flat part is contacted with a side wall of a half-case of the tape cassette and the two bent parts are respectively contacted with corresponding brakes such that the tape is effectively held without loosing the same in the tape cassette.

Abstract: A tape cassette comprises a locking mechanism for locking a cover for protecting a tape. The locking mechanism comprises a plate spring whose one end is fixed to a rib mounted on a half case and whose other end is pressed to a lock plate.

Abstract: A tape cassette reel comprises a special clamp which is fitted to a groove of a hub. The clamp comprises an upper rib, a pair of legs extended from the upper rib; a lower rib inserted between the legs and a projected part formed on the lower rib. The projected part is fitted to a cavity formed at the bottom of the groove of the hub. A tape is completely clamped on the hub by the clamp without failure.

Abstract: A video cassette tape reel comprises at least one flange; a ring hub having a groove in parallel to the axis of the hub; a clamp fitted to the groove; and peripheral guides formed in the hub between which the clamp is fitted, whereby a tape clamped on the ring hub is not contacted with the flange in winding the tape.