Patent GB-495812-A (GB)
Title: Weft replenishing mechanism for looms
IPC: D03D45/20
Filed: 1937-05-24
Abstract: 495,812. Double-shuttle looms with automatic weft replenishments. BIRD, W. F., and HEWTON, W. R. May 24, 1937, No. 14397. Convention date, Aug. 7, 1936. [Class 142 (iii)] In looms wherein the warps are formed into two superposed sheds through which respective shuttles are passed simultaneously in opposite directions so as to produce a double fabric, two superposed separate fabrics, or a double pile fabric, a transferrer 101, 100, operated through a spring by a three-armed lever 103, Figs. 1 and 9, on a shaft 99, is first moved by means of a stud 200 operating on a dagger 144 whereby a fresh bobbin 71 is transferred from a magazine into the upper shuttle 35 and the spent bobbin is expelled through the lower shuttle box. A few picks, say three, later, when the upper shuttle box at the magazine side is empty and the lower shuttle box is occupied, the transferrer is again operated, this time by a stud 201 whereby it is moved to a greater extent than before and so far downwardly as to insert a fresh bobbin in the lower shuttle. so positioned as to cause replenishment to occur when the bobbins are substantially exhausted. Transferrer construction.-The transferrer hammer 101 has a yielding spring-controlled connection with the lever 100, and the lever 103 is acted on by a spring and normally held in a retracted position in contact with the knife rail 68, a stop screw 107 limiting its forward movement. Means described are used for preventing overthrow of this lever when it is making its short stroke, Shuttle-box constructions.-Each of the compartments of the shuttle box at the magazine side has a longitudinal slot aligned with an opening in the lay to receive the ejected spent bobbins. A pivoted part 41, Fig. 7, of the front of the upper compartment is connected by clips 50 to a plate 47 pivoted on a pin 48 and forming part of the bottom of the upper compartment. A spring controlled bell-crank lever 61, Figs. 1 and 7, pivoted on a bracket 58 passes through the plate 47 and has an arm 63 carrying a roller 62. When the transferrer dagger 144 is raised into position to be engaged by the stud 201 preparatory to the replenishment of the lower shuttle, it raises a cam lever 153, which thereupon engages the roller 62 and after engaging a stop 155 turns the bell-crank lever 61 and withdraws the parts 41, 47 to provide clearance for the downwardlymoving transferrer. Initiating replenishment.-After a predetermined number of revolutions of a shaft 163, Figs. 1 and 9, driven by chain gearing from the take-up mechanism, an ear or member on a timing chain 178 on a disc 173 driven from the shaft 163 operates a lever which moves a sleeve 166 sideways on the shaft 163 to which it is keyed. A dagger 169 yieldably mounted on the sleeve is thereby so positioned that as the sleeve and shaft 163 rotate, it first engages a roller 147 and later a roller 148 on the counterweighted spring-controlled transferrer dagger 144. This is thereby moved from its central neutral position into the path of the stud 200, and three picks later, into the path of the stud 201. The disc 173, which rotates one tooth for each revolution of the shaft 163, is held in position by a roller on a spring-controlled lever 192. The ears or members on the timing chain are Magazine.-The bobbins 71 are guided in two channel members 70, 72, Fig. 12, mounted on a fixed part such as the knife rail 68. A bobbin is held in position at the bottom by spring-controlled parts 81, 83, the parts 81 being carried by a spring-controlled part 78 having a special relatively firm connection described with the guide channel 72. A cradle 90 comprising a shaft 109 having bobbinsupporting bars 110 is rocked by a bifurcated arm 108 engaging an arm 111, so that each time the transferrer is operated a bobbin is allowed to drop to transfer position. A spring-controlled latch engaging one or the other of two indentations on a sector plate on the shaft 109 holds the bobbin support in the upright position shown in Fig. 12 and also in bobbin releasing position. Weft cutting.-Shear knives 126, Fig. 5, having their blades normally opened by springs 129 are carried by a lever, which is rocked through spring devices and lever mechanism 116, 114 from the shaft 99, whereby the knives are moved forwards and after being closed by plates 53 cut the weft of the exhausted bobbin near the shuttle eye at the time of replenishment. A cam lever carried by the member 100 causes hooks on a carriage to be moved rearwardly, the upper hook engaging the weft of the upper shuttle and subsequently carrying away the cut end from the exhausted bobbin whilst the lower hook acts similarly on the lower weft. A selvage cleaner, which may be operated by the lay, removes the weft end of the exhausted bobbin and the weft end from the first pick from the selvage. Picking-mechanism.-Each picker stick is pivoted on a short shaft and is controlled by a spring, a foot being engaged by a spring counterbalanced treadle arm, which is operated by rollers adjustably mounted on a doublearmed member on the low shaft. In the Specification as open to inspection under Sect. 91, it is stated that the invention may be used in looms wherein the shuttle boxes do not oscillate with the lay, and in looms wherein a replenishing unit is mounted on each side of the warp shed, the upper shuttle being refilled on one side, and the lower shuttle on the other side. This subject-matter does not appear in the Specification as accepted.