GB713141A - Improved clutch arrangement preferably for presses - Google Patents

Abstract

713,141. Friction clutches. KNOCHL, L. July 17, 1952 [July 17, 1951], No. 18110/52. Class 80 (2) Engagement of an expanding-ring clutch 7 between a driving wheel 2 and a member 1 secured to the shaft 5 of a press or like machine is produced by engagement of an auxiliary friction clutch between the face of wheel 2 and a member 12, which latter has a recess 11 engaging one end 9" of a lever 9 pivoted at 10 in the member 1, the other end 9' of the lever acting on the ring 7. Member 12 is connected by rollers 23 engaged in inclined recesses 24 to a member 25 connected by a spring- loaded friction coupling 29, 30 to a ring 31. When ring 31 is free, an arcuate spring 32 produces relative rotation between member 12, 25 and springs 21 cause engagement of the auxiliary clutch which then moves lever 9 to engage the clutch 7. When rinig 31 is held fast by friction clamps 52,53 tiltably mounted on a pivoted arm 46, member 12 continues to rotate, rollers 23 causing it to be retracted from wheel 2, thus allowing disengagement of clutch 7 until the rollers reach the end of the recesses 24, whereupon member 25 is carried along and the friction coupling 29, 30 brakes the shaft 5 to rest through the lever 9. Arm 46 is normally held by a spring 56 in position to hold ring 31 fast. One arm 65 of a bell crank lever is connected at M to a pedal, the other arm 66 carrying a pivoted catch 44 normally held by a spring 71 in engagement with a projection 45 on arm 46. On depressing the pedal to start the press, catch 44 pulls arm 46 to the left, so freeing the ring 31. During the ensuing revolution of shaft 5 the catch 44 is released from the projection 45 by means of a roller 42 carried by shaft 5 and coacting with a lever 43 which tilts the catch 44 through a rod 72, but the return movement of arm 46 te the right is prevented until the top of the press stroke by a lever 61 co-acting with a cam 40 on shaft 5. Rod 72 may, when required, be tilted, to the left out of the path of lever 43, so as to allow the press to operate until the pedal is released.