GB679245A - Improvements in or relating to tractor clutches - Google Patents

Abstract

679,245. Ratchet clutches. FORD MOTOR CO., Ltd. Jan. 31, 1951 [Feb. 18, 1950], No. 2465/51. Class 80 (ii). [Also in Group XXXI] Relates to a clutch in a tractor driving gear (see Group XXXI) arranged between the output shaft 31 of a change speed gear and a rear axle driving shaft 33. The clutch comprises drums 44, 47 in splined engagement with the shafts 31, 33 respectively, the drums having annular extensions abutting and held in spaced relationship by a shaft 48. The extensions have interior and exterior frictional surfaces adapted to be engaged by helical springs 57, 66 to transmit the drive, the spring 57 operating for the one direction of rotation of the shaft 31 and the spring 66 for the reverse rotation, the springs being wound in opposite hands. The spring 57 is secured at 59 to the drum 47 and has a tapered forward portion adapted to be engaged by a throw-out collar 63 which is normally urged rearwardly by a coil spring 64 so that the spring 57 wraps itself onto the exterior frictional surfaces of the drums 44, 47 to transmit the drive between the shafts 31, 33, the collar 63 being movable to the left in Fig. 3 by a lever 84, Fig., 2, to disengage the drive. The spring 66 is secured at one end to the drum 47 and is expanded to engage the interior frictional surfaces of the drums 44, 47 by means of an energizing spring 69 which is normally in light frictional engagement with the drum 44 so that, on the shaft 31 rotating in the reverse direction, the spring 69 expands to enable the drive to be transmitted between the shafts 31, 33. By means of a pawl 86 on the lever engaging ratchet teeth 87 on a pivoted and spring urged lever 88 the forward drive clutch is held disengaged. The pawl 86 and ratchet teeth 87 are disengaged after a main clutch between the tractor engine and the change speed gear has been disengaged by the rod 94 connected to a pedal 97 controlling the main clutch and engaging an arcuate slot 93 in the lever 88, movement of the pedal 97 after the last motion has been taken up moving the lever 88 against the action of the spring 91 and allowing the lever 84 to return to its clutch engaged position under the action of a spring 98 so that the forward drive clutch can not be re-engaged until the main clutch has been disengaged.