| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve reliability of a product by vertically providing a first gear engaged with a second gear in a hollow pipe on a motor shaft perpendicular to the supporting grooves on the inner face of a lower drum and the upper part of the drum, and supporting the inside of a clutch ball with a plate so as to face outwards and the outside with a bar-like spring so as to face inwards. SOLUTION: When electric power is supplied to a motor, clutch balls 14 arranged inside against a clutch spring 15 and supported with the supporting pieces 13a of a plate 12 fixed to a motor shaft 11a at the inside, are separated by centrifugal force, and inserted into supporting grooves 30 formed on the inner face of a drum 3. A first gear on the lower end part of the drum 3 and a second gear in a hollow pipe are rotated in order, and a third gear fixed to a rod on the output side is elevatably moved. At ascending it is unlocked, and at descending it is locked. When the clutch balls 14 are opened by centrifugal force, because the elastic force of the clutch spring 15 is weak, they are easily inserted into and supported with a plurality of the supporting grooves 30 provided on the inner part of the drum 3, so as to prevent malfunction from generating and improve reliability of the product.</p> |
