Patent GB-785137-A (GB)
Title: Improvements in or relating to textile drafting mechanism
IPC: D01H5/74
Filed: 1955-06-14
Abstract: 785,137. Textile drafting mechanism. SACO-LOWELL SHOPS. June 14, 1955 [Aug. 17, 1954], No. 17157/55. Class 120(2) Textile drafting mechanism comprises a series of  bottom rolls, a co-operating series of top rolls, means locating the rolls to act successively on a sliver, a weighting arm overlying the top rolls, and at least one top roll weighting unit which comprises a housing mounted on the weighting arm, a plunger movable into weighting engagement with one of the top rolls, a compression spring acting against the plunger and a plug against which the spring is seated, which plug is screw threaded into the housing for adjustment and has an aperture through which a stem portion of the plunger extends, and a stop motion actuating device comprising an electrical contact member above the stem portion and arranged so that when it is engaged by the stem portion, an electrical contact is established. In the arrangement shown bottom rollers 10, 12, 14, 16 and 18 and top rolls 24, 26, 28 and 30 are mounted in slides 20 carried on roll stands 22. Each top roll assembly has a single series of weighting units 21, 31, 41, 51 which engage against one end only of each top roll, a separate identical over-arm assembly being provided to engage the opposite end of each top roll of the series. Each weight unit comprises a plunger 36 which acts against the sleeve of the top rolls 30 the plunger 36 being supported within a housing 40 and formed with an upwardly extending stem portion 42. A compression spring 46 forces the plunger yieldably downwards against the top roll the pressure being exerted being adjustable by turning the threaded plug 44. This unit may be further constructed and arranged to cause a stop motion of the machine to operate in the event of any individual plungers 36 being forced upwardly by an abnormal thickness of sliver passing or by a lap building up on the associated top roll. For this purpose a conductor 52 is arranged above the stem 42, the conductor 52 being engaged by a spring arm 60 connected in the electric circuit for the stop motion of the machine. The individual weight and stop moton units are mounted on a frame which comprises a pair of bars 70 and 72 which pass through slots formed in the lower portion of each weighting and stop motion unit housing 40, leaf springs being provided to maintain the units in readly adjustable positions on the bars. At one end the two bars 70 and 72 are connected to one another bv a yoke 78 which in turn is connected by a pin 80 with a vertically extending rod 82 slidably mounted in a tubular guideway 84 in a support slide 86 mounted on roll stand 22. At its lower end the rod 82 is slotted to receive a horizontally disposed arm 88 which is pivoted at 90 on the roll stand 22. At their other ends the arms 70 and 72 are connected to the bottom arm 88 by means of a contractable self-locking device which comprises a link 92 pivoted to the forward end of the arm 88 and a hook member 94 which is adapted to engage a cross pin 96 extending between the two arms 70 and 72 at their forward ends. The link 92 and hook member 94 are connected together by means of tan eccentric locking device consisting of a disc 98 pivotally mounted by a pin 99, the disc being provided with an operating handle 100. Rotation of the disc clockwise causes the link 92 and hook 94 to be drawn together into a self-locking position as shown in Fig. 1. Rotation of the disc in the opposite direction effects release of the pressure exerted by the several units simultaneously. This is achieved through the rocking movement imparted to the arm 88 about the pivot 90 when the link 92 and hook 94 are moved relatively apart by the rotation of the disc 98 so that the rod 82 and hook 94 move upwardly thus relieving the loading from the top rollers.