| 摘要 |
PURPOSE: To quietly carry out the change of belt tensile force by arranging a spiral auxiliary spring on a ratchet rotatably installed between a belt reel and a winding spring and providing a brake system to delay the rotation of the ratchet with the auxiliary spring as a driving source. CONSTITUTION: An inner end of a spiral auxiliary spring 22 is engaged with an outer periphery of a driving sleeve 18 on which a belt reel 12 rotatably installed on a housing 10 of a belt winder is fixed, and an outer end of this auxiliary spring 22 is connected to a ratchet 24 rotatably installed, on a pin 28 integrated with a housing cap 30. A click (not shown in the drawing) actuated by an electromagnet 36 is engaged and disengaged with a stop tooth 32 of the ratchet 24. Additionally, an inner end of a spiral winding spring 38 is engaged with an outer periphery of a hub 26 of the ratchet 24, and its outer end is fixed on the cap 30. Thereafter, a plural number of engagement members 40 with the auxiliary spring 22 as a driving source are pivotally installed 42 on one side surface of this ratchet 24, made to cooperate with a friction disc 44 installed on the driving sleeve 18 and made to function as a brake system. |
