The present invention relates to an automatic-reverse tape player, and more particularly to an operation switching mechanism for use in such an automatic-reverse tape player.
Automatic-reverse cassette tape players are widely used in automobiles. Many of these automatic-reverse cassette tape players have a common motor for rotating capstans and reel bases for the purpose of saving electric energy. In ordinary cassette tape players, the rotational speed of a reel base varies depending on the diameter of the tape being wound or unwound on the reel base in a play mode in which the tape is fed at a constant speed by a pair of capstans and a pair of pinch rollers. A slip mechanism is associated with the reel base for allowing the tape that is fed at the constant speed by the capstans and the pinch rollers to be wound on the reel base without being slackened or excessively tensioned.
The tape transport mechanism of an automatic-reverse cassette tape player has a pair of slip mechanisms associated with the respective reel bases for feeding the tape at a constant speed in opposite directions. When the tape is fed at the constant speed, rotational forces are transmitted from one of a pair of flywheels rotated in different directions by one capstan motor selectively to one of the slip mechanisms associated with the respective reel bases depending on the direction in which the tape is transported. A pair of intermediate rotatable idlers is disposed between the pair of flywheels and the pair of slip mechanisms. The pair of flywheels and the pair of intermediate rotatable idlers make the entire mechanism complex and result in an increased number of parts. Since the intermediate rotatable idlers are spaced from each other, delicate timing has been required to control the switching between the intermediate rotatable idlers in synchronism with the switching between the pinch rollers, and it is tedious and time-consuming to adjust such timing.
It is widely known to control the switching between the directions in which the tape is transported, the switching to a fast feed mode, and the loading and ejecting of the tape with a combination of a reversible control motor and cam gears. For example, there is known a switching mechanism for effecting the above switching operations with an intermediate cam gear swingable into mesh with one of the cam gears, each having tooth-free regions, depending on the direction in which the control motor rotates.
With the known structure, the cam gears are concentrically stacked one on the other, and hence are of a complex structure as a whole in their transverse direction. Furthermore, the cam gears do not have a large layout freedom as various members of the switching mechanism and the cam gears are coupled to each other in one position. It has been difficult to achieve delicate timing for controlling reciprocating movement of the loading and tape transport mechanisms while the cam gears are reciprocally rotating through about 360.degree..