Patent GB-190718313-A (GB)
Title: Improvements in Circular Knitting Machines.
Inventor: BARRATT WILLIAM THOMAS
Filed: 1907-08-13
Granted: 1908-04-23
Abstract: 18,313. Barratt, W. T. Aug. 13. Circular knitting-machines of the kind described in Specifications No. 28,018, A.D. 1896, No. 4883, A.D. 1897, and No. 15,764, A.D. 1898, having two conical rotary needle beds and controlling-apparatus whereby royal rib, welts, and slack courses may be knit at predetermined intervals are provided with adjustable sinker and presser wheels capable of being put out of action by a stop-motion. The yarn is sunk on the bearded needles of the lower bed by a sinker wheel, and is taken and shared by the needles of the upper bed. The sinker wheel is geared to the needles, and the sliding or other sinkers carried by it are operated by a stationary cam plate. The central stud 73, Fig. 4, on which the sinker wheel revolves is held adjustably clamped in a slotted portion of a rocking frame 74, which swivels in a base 80 and can be raised or lowered by adjusting- screws. The sinker cams are mounted on a block 90 attached to an adjustable slide plate fitting loosely round the central stud 73, the amount of adjustment being shown by an index finger. The sinker .wheel is held up to the needles in the normal working of the machine by the light pressure of a flat bent spring 125 against a tail 124 attached to the frame 74. If for any reason the sinker wheel is prevented from rotating, the movement of the needles swings the whole frame 74 aside on the pivot 79, past the spring 125. The same movement puts the fixed presser also out of action and prevents the work from running off the needles. This presser is formed by the bent flattened end 132 of a cylindrical sliding rod 133 which is pushed back against the pressure of a spring by a cam-shaped lever 43. This acts on a bracket 137 attached to the rod and is operated by the movement of the sinker-wheel frame 74. The same movement also puts mechanism into action for stopping the machine. A wheel carrying a number of pivoted arms 149, Fig. 9, is journaled below the lower needle bed and connected by a slide to a trip-mechanism for releasing a spring-operated belt-shipper which can be worked independently by hand. Each arm 149 is retained in position against the pull of a spring by a dog 177 fixed to a rotatable rod 168 provided with a torsion spring. This rod has attached to it a stud 175, Figs. 4 and 9, which is engaged by the spring 125 when the sinker-wheel frame 74 is moved aside, but the rod 168 can also be rotated, for the purpose of stopping the machine, by a device 179 bearing on the web, and operated whenever the work runs off the needles. The finger 179 slides in a support 180 fixed to the rod 168, and is rigidly attached to a lower spring-pulled sliding finger 182, which is normally out of action. When a hole occurs in the fabric, the slides 179, 182 move forward until the latter engages the needles, whereupon the rod 168 is turned and the machine stopped. There is also a projection fixed to the support 180 which runs over the fabric and rotates the rod 168 whenever a bunch of yarn or fabric is encountered. The controlling-apparatus by which the formation of slack courses, royal rib, and welts is determined comprises two pattern chains and intermediate connexions and inclines whereby three separate studs carried along with the upper bed are set at the proper elevation for putting in and out of action various stationary apparatus. The two pattern chains normally move on together, being driven by pawls attached to the same driving-arm, but the chain which controls the change of work rests at intervals and is put into action after a predetermined number of courses by the other chain, which advances at each revolution of the machine. The studs 244, 245, 246, Fig. 4, act on one or other member of pairs of levers such as 256, 258, Fig. 19, which are placed in their paths. These levers are pivoted at 257 and 259, respectively, to a base, and are connected together by the engagement of a pin 262 on one lever with a pair of pins 261 on the other, the three pins being confined in a slot 260. Thus, when a slack course is to be made, the pattern mechanism causes the pin 244 to rise to its highest position, where it engages the upper lever 290 of a pair. The outer end of the deflected lever 290 is inclined and pushes out the upper end of a bellcrank 297, the lower end of which is connected to the out-throw cam of the sinker wheel, and causes long loops to be sunk on the lower needles. The pin 244 also engages a projection on another pair of levers connected in an analogous manner to a swinging portion of a depressing cam for the upper needles, so that the upper needles are not projected at this point. When royal rib is to be made, the pin 245, Fig. 8, is elevated until it engages a lever 306, which in turn bears on a pin 314 attached to a vertical shaft 311 and causes a cam 316 at the lower end to throw out the rotary presser for the upper needles. A similar presser at the other side of the cylinder remains in action. A welt is made when the lowest stud 246 rises, and engages two similar sets of levers for throwing out both the welting cam and the slack-course cam, leaving the knitting to be performed by the lower needles only. The pin 246 also engages a lever 292, Fig. 4, and releases the bell-crank 297 to which is attached the sinker out-throw cam, so that short loops are sunk on the needles. The pin 246 also engages a lever 308, Fig. 8, which, acting on a pin 315 attached to the shaft 311, throws out the rotary pressers. The lever 309, which is attached to and moved by the lever 308, moves away from a pin attached to a bell-crank 323 connected to the stitch cam of the lower needle-cylinder, whereupon the pull of the knitted web draws the stitch cam up to the highest position corresponding to the shortness of the loops sunk by the sinker wheel.