Brake mechanism for drum type magnetic recording and reproducing apparatus

A brake mechanism for drum type magnetic recording and reproducing apparatus including:

• first and second reels each having:
• a pivot vertically mounted on a base plate of said magnetic tape machine;
• a first gear rotably mounted on said pivot;
• a first reel body coaxially and rotably fitted to said pivot with said first gear;
• a first frictional device providing a frictional force between said first gear and said first reel body, said first gear is structured such that when said first gear is put in rotation, said fist gear drives said first reel body in rotation to produce a braking force therebetween;
• a reel motor for providing power necessary for said first reel or said second reel to drive a reel of said cassette;
• a rocking gear mechanism mounted between said first and second reels, including:
• a drive gear being driven by said reel motor in rotation;
• and a rocking arm having a first end and a second end, said first end having a pinch swingingly pivoted on said base plate, a transmission gear rotably mounted on said pinch for engaging with said drive gear;
• and said second end having a rocking gear pivotally connected thereto for engaging with said transmission gear, and selectively engaging with said first gear or said second gear in accordance with a swinging of said rocking arm;
• and first friction means for providing a frictional force between said rocking gear and rocking arm;
• said transmission gear wherein said transmission gear is driven by said drive gear in rotation, and is structured such that said rocking arm is first driven in rotation to cause said rocking gear to be selectively engaged with said first gear of said first and second reels and then in rotation opposite said transmission gear;
• a brake plate coaxially mounted with said rocking gear on said second end of said rocking arm, and second frictional means for providing a frictional force between said brake plate and said rocking gear to cause said rocking gear to drive said brake plate in rotation;
• a first clutch tooth provided on said brake plate for engaging with said first gear of said first reel when said rocking gear is engaged with said first gear of second reel;
• and a second clutch tooth for rotably engaging with said first gear of said second reel when said rocking gear is engaged with said first gear of first reel;
• wherein said rocking gear and said first and second clutch teeth are structured to match an operating mode of said magnetic tape, causing said first and second reels to provide a varying brake force and thus a varying back tension on the tape.