| 摘要 |
<p>PURPOSE:To quickly obtain a normal engaging state of gears even if the tips abut on one another when the gears are engaged. CONSTITUTION:This device is provided with an idler gear 35 which can be engaged with either a driving-side gear 23 and a reel-bed 26 on one side or a driving-side gear 24 and a reel-bed gear 27 on the other side in such a manner that the idler gear 35 can freely contact with or separate from the rest of the gears and the former can be engaged/disengaged with the latter. The tape feeding direction can be switched by switching the engagement of the idler gear 35. The driving-side gears 23, 24, a pair of reel-bed gears 26, 27 or idler gear 35 are formed so as to have constant curvature from the deddendum circle to the addendum circle, while at least one of the driving-side gears 23, a pair of reel-bed gears 26, 27 and the idler gear 35 is formed in such a way that the tooth profile, in which a part ranging from the vicinity of the pitch circle to the addendum circle is missing, appears intermittently. With this contrivance, a noise is rarely made, and malfunction can be avoided. In addition, restrictions in designing can be reduced, and sure engagement can be obtained by means of simple constitution.</p> |
