GB845725A - Variable speed control for spinning and similar machines - Google Patents

Abstract

845,725. Spinning &c. machines. SHUFORD MILLS Inc. July 2, 1957 [Jan. 22, 1957], No. 20842/57. Class 120(2). [Also in Group XXIV] In a spinning &c. machine having a reciprocating traverse and winding spindles driven from a common shaft, a variable-speed drive is coupled to the shaft and is operated by a fluid-pressure system including a regulator valve, means being provided which respond to movement of the traverse in one direction to open the valve and to movement in the opposite direction to close it. In the ring-spinning machine shown, packages are wound on bobbins having cone-shaped lower portions so that the diameter of the package decreases on the up-stroke and increases on the downstroke of the traverse; the aim being to decrease the speed of winding on the up-stroke to avoid placing the yarn under tension, and to increase the speed on the down-stroke. The spindles and the builder-motion are driven from a shaft 16 to which a variable-speed drive is transmitted from a motor 60 through pulley pairs 74, 61 ; the upper pair are each of the expanding-type described in Specification 845,722 and the motor is resiliently mounted e.g. as described in Specification 845,724. The pulleys 61 expand or contract under control of a piston on a cylinder 102 which in turn is controlled by a valve 120 operated by a lever 150 linked at 151 to a pivoted extension of the arm of the builder motion at 30, which extension moves down as the arm moves up with each downward movement of the ring-rail and vice versa. With each down movement of the extension the link is pulled to move the arm 150 to the right and gradually to open the valve 120 and admit air under pressure to the cylinder 102 to enlarge the effective diameter of the pulleys and increase the speed of the drive. With each up movement of the extension, a spring 154 in the link, tensioned during the down stroke, is relaxed to allow the arm 150 to move to the left and close the valve, whereby the air supply is cut off and a subsidiary valve opened gradually to exhaust the pressure in the cylinder. The subsidiary valve is adjustable to determine either the maximum or the minimum spindle-speed; in the one case it can be adjusted to open to exhaust the pressure when it attains a level to correspond to the desired maximum speed; in the other case, it can be adjusted to close when the pressure falls to correspond to the desired minimum speed. The maximum and minimum speeds may also be determined to some extent by the stroke of the piston. When it is desired to build "bunches" at the foot of the spindle instead of using bobbins with coneshaped bottoms, the valve 120 is caused to remain open for winding to proceed at uniform minimum speed. To this end, the link 151 can be disconnected: or a valve can be interposed on the pressure line to be opened by a solenoid through a switch which is operated only after the desired number of strokes have been made by the traverse.