Patent GB-582046-A (GB)
Title: Improvements in or relating to automatic winches
IPC: B66D1/14
Filed: 1944-02-18
Abstract: 582,046. Brakes. ALL AMERICAN AVIATION, Inc. Feb. 18, 1944, No. 3072. Convention date, Jan. 16, 1943. [Class 103 (i)] [Also in Groups XXX, XXXII and XXXIII] A winch, particularly suitable for winding on .and off a cable connecting aircraft to other bodies, comprises a drum 32 running in bearings 61 on a shaft 63 itself mounted in bearings 65, 66 on a frame 25, 26. A disc brake 35 is carried by a support 33 and arms 58 keyed to the shaft 63 and is operated to connect the drum 32 to the shaft 63 by fingers 74 pivoted at 75 to posts 72 extending .from a pressure ring 73 integral with the drum 32. The inner tips of the fingers 74 bear on a disc 96, the position of which is determined by a rod 97 carrying a collar 98 between which and the disc 96 a spring 99 is interposed. A spring 113 abutting against a shoulder 116 draws the rod 97 to the left as far as is allowed by an adjusting nut 105 fitted with an indicator sleeve and cup 111, 112 and having side trunnions 122 mating with the slotted ends of a yoke 118 swinging at 119 on a lug 120 projecting from the frame member 26. The upper slotted ends of the yoke 118 are engaged by side pins mounted on a nut 138 which can take up an outer position clear of a thread 135 or can be brought into engagement with said thread at any stage of the off-wind by turning a handle 145, the handle knob being first pressed toward the drum 32 so that the handle pivots about a point 146 and frees a tail 147 from locking together the inner and outer sleeves of the nut 138. Rotation of the handle 145 screws the nut 138 along the thread 135 till end inclines 159 engage pins 157, and the position of these pins may be selected by a spring plug 155 which can enter one of a series of holes 160 in a stationary plate 128. The' thread 135 is formed on a shaft 125 geared by pinions 130, 131 so as always to rotate with the drum 32. As the brake is gradually applied till it reaches its full effect by the offscrewing of the nut from the thread 135, the number of turns the drum will make before such application begins will depend on the initial position of the nut as determined by the pins 157. The spring 99 gives a slight initial braking effect on the drum to prevent over-running. A motor is employed to wind in the cable 12, a disk brake on the motor shaft functioning to hold the support 33, and also the motor shaft, rigid while the cable is being unwound. The brake is taken off when a solenoid is energized, this taking place simultaneously with the excitation of the motor. The cable is secured to the drum 32 by an end piece 161 perforated to take over a pin 162 screwed into the barrel. A readily sheared split pin 163 keeps the piece 161 normally in place, but gives way if the cable becomes completely unwound and pulls outward. The tow cable is of plastic rope to give further cushioning to the applied pull. Hand operating means for both the drum 32 and the motor are provided. In order that the cable may wind. evenly on the drum, a traveller may be provided reciprocating under the control of a crossthreaded shaft geared to the drum. The threadengaging nose may be drawn out of the threadgroove and held by a ball-snap to permit the traveller to be adjusted to any position. The whole winding guide may be swung upward and held in non-operative position. The support 33 is held against accidental rotation in the unwinding direction by a pawl engaging ratchet teeth 34, the pawl being withdrawable by a handle Means may be provided for quick release of the main brake by pulling a cord which takes the pull of the spring 113 off the rod 97.