text: 1. Field of the Invention
  This invention relates in general to a tape cassette and more particularly to an improved tape cassette which can be horizontally inserted and removed from a tape machine.
  2. Description of the Prior Art
  Conventional compact tape cassettes are illustrated in FIG. 1 which comprises a plan view wherein the upper half of the cassette casing has been removed. In FIG. 1, a lower half of the cassette casing 1 has a central opening portion 2 formed at the front surface side. Openings 3a and 3b are arranged in symmetrical positions of the front surface and small windows 4a and 4b are located on both sides of the central opening 2. Partition plates 5a and 5b separate the right and left opening portions 3a and 3b from the inside of the lower half 1 of the tape cassette and capstan insertion through holes 6a and 6b are formed for receiving the capstan therein. Positioning openings 7a and 7b are formed in the cassette and a pad 8 is attached to a resilient spring member 8' within the central opening portion 2. Erase preventing concave portions 9a and 9b are formed in symmetrical positions at the rear of the lower half of the cassette 1.
  Hubs 10a and 10b are mounted symmetrically within the lower half 1 and upper half of the cassette and the hubs 10a and 10b are positioned by inner surface rims not shown of the upper and lower halves of the cassette casing and are arranged to have predetermined axial distance therebetween. When the cassette casing is loaded into a tape recorder, reel shafts 14a and 14b are inserted from the underside of the cassette casing into the hub apertures 11a' and 11b' and a capstan 15 is inserted from the underside in the capstan through the openings 6a and 6b positioning pins 6a and 6b are received within the positioning openings 7a and 7b respectively, so as to accurately position the tape cassette. During record or playback mode of the tape recorder, the tape T is transported by a pinch roller 17 which is inserted from the front surface of the cassette into the opening 3a and 3b which is provided at both sides of the central opening 2 so as to press or grip the tape T against the capstan 15 so that the tape 15 will be driven by the capstan 15 from a tape supply reel which is normally mounted on the left hand hub 10a and the tape is transported by a guide pin 12a, a guide roller 13a and over a front tape path by a record and/or playback head 18 which is in close contact with the tape and is then delivered by a guide roller 13b and a guide pin 12 b to the take-up hub 10b where it is wound. An erase head 19a is illustrated in FIG. 1.
  Since the tape cassette is loaded and/or unloaded to or from the tape recorder in the axial direction of the reel shafts 14a and 14b and the capstan 15 and due to positional deviations in the tape cassette, clearances have been provided in prior art cassettes between the lower half of the cassette casing and the hubs 10a and 10b, respectively. Additionally, such clearances are provided for the rotary drive between the engaging projections 11a' and 11b' of the hub apertures 11a and 11b formed within the hubs 10a and 10b and extensions 14a and 14b of the reel shafts 14a and 14b into which the reel shafts 14a and 14b are engageably inserted.
  When the tape T is transported and rewound, it is possible that the hubs 10a and 10b will swing relative to each other and the tape T can be injured when it is wound with the edge portion of the tape contacting the inside of the upper and lower halves of the cassette casing to cause damage and also to result in a deteriorated audio signal during record or playback operation. Due to the clearances in the rotary direction between the engaging extensions 11a' and 11b' of the hub apertures 11a and 11b of the hubs 10a and 10b and the projections 14a' and 14b' at the reel shafts 14a and 14b causes a servo response when the tape T starts to run and is stopped and this is very undesirable and unsatisfactory.
  Also, since when the tape cassette is loaded or unloaded into or from the tape recorder in the axial direction of the reel shafts 14a and 14b and the capstan 15, it is required that the tape recorder be provided with a loading and/or unloading mechanism for loading and unloading the tape cassette and the construction of such apparatus becomes very complicated and the loading and unloading of the tape cassette becomes very difficult particularly for an automatic changer mechanism for the tape cassette. An extremely complicated mechanism is required for an automatic change and thus the conventional tape cassette is unsuitable for use wth automatic changer mechanism.