Abstract: At the time of crimping and fixing a plastic lens on a lens barrel, productivity is improved by achieving an accurate alignment and a reliable crimping. Fixed protrusions are arranged on an outer peripheral portion of the lens at intervals capable of providing three-point support, and a fixed protrusion is arranged on a line connecting the fixed protrusion and the center of the lens, a reference hole corresponding to one of the fixed protrusions includes an opening having substantially the same size as that fixed protrusion, and the other fixed protrusions have substantially the same size and fit in loosely fitting holes. The loosely fitting holes corresponding to the fixed protrusions include larger openings than the fixed protrusions and an elongated hole corresponding to another fixed protrusion is provided in such a manner as to be elongated along a direction of the reference hole.

Abstract: At the time of crimping and fixing a plastic lens on a lens barrel, productivity is improved by achieving an accurate alignment and a reliable crimping. Fixed protrusions are arranged on an outer peripheral portion of the lens at intervals capable of providing three-point support, and a fixed protrusion is arranged on a line connecting the fixed protrusion and the center of the lens, a reference hole corresponding to one of the fixed protrusions includes an opening having substantially the same size as that fixed protrusion, and the other fixed protrusions have substantially the same size and fit in loosely fitting holes. The loosely fitting holes corresponding to the fixed protrusions include larger openings than the fixed protrusions and an elongated hole corresponding to another fixed protrusion is provided in such a manner as to be elongated along a direction of the reference hole.

Abstract: A tape-loading mechanism of a magnetic recording and reproducing apparatus according to the present invention has a tape travel system in which a magnetic tape drawn out of a supply-side tape reel is helically wound around a drum along a lead thereof by tilted guides respectively provided on inlet and outlet sides of the drum and tape guides respectively provided on inlet and outlet sides thereof, passed via a capstan and wound around a takeup side tape reel. A vertical position of the lead of the drum is set equal to that of a lower edge of the tape in a state immediately before the magnetic tape is loaded onto the drum. The magnetic tape is twisted in the middle of the tape travel system in order to cancel difference in tension between upper and lower edges of the magnetic tape when the magnetic tape is loaded onto the drum.

Abstract: A recording and reproducing apparatus has an indirect drive arrangement in which the reel turntables are rotated by an existing motor, such as a capstan motor or the like. The reel turntables can pivot about supporting points on a chassis such that they can be moved between large and small cassette driving positions. A drive gear supported on a swing arm and which is driven by a capstan motor, is selectively meshed with one of the driven gears provided on the two reel turntables.

Abstract: A recording and/or reproducing apparatus includes a rack mechanism by which a cassette compartment can be easily removed from a mechanical deck regardless of any position at which reel tables are moved. In a recording and/or reproducing apparatus such as a video cassette recorder in which a space between two reel tables can be moved by a reel table movement mechanism and small and large tape cassettes of different size are selectively mounted on the reel tables, a rack mechanism has a pair of parallel racks which can be relatively moved through a pinion, one rack has an engagement recess formed on one end portion thereof, the other rack has an engagement recess formed on one end portion thereof, the engagement recess being positioned over the one rack and a cassette compartment includes a drive lever which is moved in the height direction in response to the insertion of tape cassettes of different size.

Abstract: To provide a recording and reproducing apparatus which permits to use tape cassettes different in not only size but also thickness. In order to make the apparatus cope with the tape cassettes different in size and thickness, there is provided a positioning guide mechanism including a pair of positioning guide members so that a small cassette can be guided at both the side faces on a cassette supporting surface of the cassette holder so as to be depressed and projected by a biasing means, and a pair of side plates at its both sides of a cassette holder so that a large cassette can be guided at its both side faces. If a user is not highly skilled in operating such recording and reproducing apparatus which permits to use tape cassettes different in size and thickness, the apparatus will suffer from risk that the cassettes are erroneously inserted or the user carries out malicious operation.

Abstract: A recording and reproducing apparatus can translate a detecting device for detecting information, such as the kind and content of tape cassette and a reel lock mechanism releasing device to proper positions corresponding to tape cassettes of different sizes. A tape cassette information detecting device (71) and reel lock releasing device (72a, 72b) can be translated to positions at which large and small tape cassettes are in use through a swing drive member (54), a translating lever (73), a driving link (74), a detection mechanism holding member (75) and a reel lock releasing plate (77) in unison with a movement of reel mounts (44, 45).