1. Field of the Invention
The present invention relates to a tape recorder for recording and reproducing signals (image, sound, character, and the like) on a recording medium such as magnetic tape. More particularly, the invention relates to a pinch roller apparatus for a tape recording/reproduction device, which can prevent the deterioration of picture quality caused by the adhesion of foreign objects to the recording medium, by providing a cleaning device for eliminating foreign objects adhered to the circumferential surface of the pinch roller which helps to feed the recording medium.
2. Description of the Related Art
In a conventional tape driving apparatus, illustrated in FIG. 1, a tape 200 extracted from the supply reel 20 of a cassette 100, which is positioned in opposition to head drum 10, is guided by a tension shaft and tension poles 30a, 30b of a supply guide device and guide roller 30c and slant guide 30d. The tape 200 is then caused to slide along the circumferential surface of a recording/reproduction blanking head 40 at a predetermined slant angle. The tape 200 is then guided by a plurality of guide means such as a slant guide 40a, a guide roller 40b, a tape guide 40c and a review arm 40d and is caused to wind around the take-up reel 60 after passing along an audio control head 50. A capstan 70 and a pinch roller 80 are provided in opposition to one another so as to impart a feeding force to the tape 200 at a position between the audio control head 50 and the take-up reel 60.
In the conventional tape driving apparatus described above, the tape 200 is held against the head drum 10 by guide means while the cassette 100 is positioned by a cassette loading apparatus (not shown).
In other words, the tape 200 is guided from the supply reel 20 of cassette 100, by a plurality of supply guide means 30a, 30b, 30c, 30d, and then contacts the circumferential surface of head drum 10 after passing a blanking head 40 at a predetermined slant angle. The tape 200 is then caused to be wound around the take-up reel 60 of the cassette by guide means 40a, 40b, 40c, 40d after passing the audio control head 50.
As illustrated in FIGS. 1 and 2, the pinch roller 80 is provided at a position between the audio control head 50 and the take-up reel 60 for pressing the tape 200 against the circumferential surface of the capstan 70. The pinch roller 80 is supported at the free end of a pivotable lever 90. The capstan 70 is caused to rotate by a capstan motor so as to impart a feed force to the tape 200.
However, in such a conventional tape driving apparatus, foreign objects which have settled on the tape tend to stick to the pinch roller during a recording or playback operation. Similarly, the foreign objects adhered to the pinch roller during recording tend to stick to the tape again when the tape is fed in reverse, such as during a rewind operation, for example. As a result, the head may be damaged and undesirable noise may be generated during a playback operation.
Japanese laid open utility model Application No. Hei 2 (1990) 101309 discloses a technique for cleaning the head of a tape recorder by pressing a cleaning member against a rotating drum operation. Also, Japanese laid open utility model Application No. Hei 3-5212 discloses a technique in which a member for cleaning a magnetic head is mounted on a pole base.
However, because neither of the above-referenced applications disclose a technique for cleaning the pinch roller, it is inevitable that noise will be generated due to contamination of the head by foreign objects which have previously adhered to the pinch roller.
U.S. Pat. Nos. 4,580,185 and 4,498,115 disclose various techniques for preventing the above-mentioned problems.
In particular, the first of the above-mentioned U.S. patents discloses a capstan which is cleaned by a dedicated cleaning cassette. The pinch roller is placed in contact with a pad of the cassette, and the ribbon of the cassette is placed in contact with the head drum and audio head. Accordingly, the capstan, pinch roller, head drum and the audio head are cleaned when the cleaning cassette is inserted into the cassette loading apparatus.
In the second of the above-mentioned U.S. patents, the housing of a dedicated cleaning cassette has a felt pad attached thereto. The felt pad is placed in contact with the capstan so as to clean the capstan.
However, these references both require the use of separate cassettes for cleaning and are thus inconvenient.