| 摘要 |
<p>A safety overlatch clutch 14, forming part of a drive train of a hand tool, has two clutch elements, a spur wheel 18 with a detent curve 16 and a clutch disc 20 which are connected to each other by a set of rollers 22. The rollers 22 are pushed out of a groove 28 in the clutch disc 20, by compression springs 30, and jam into the detent curve 16. As the clutch rotates, the detent curves 16 push harder against the rollers 22 until, at a preset torque, the curve 16 pushes the rollers 22 in to the grooves 28 and the spur wheel 18 and clutch disc 20 are disconnected. The torque at which this happens can be varied via a plunger 36 having a tapered surface 56, which can increase or decrease the bias in the compression springs 30 by moving spring plungers 32. The plunger is operated by a rotary lever 46.</p> |
