GB245308A - Improvements in or relating to dobbies for looms for weaving - Google Patents

Abstract

245,308. Place, J. H. Feb. 26, 1925. Dobbies.-An open shed dobby has double armed peg levers b<1>, b<2> with hubs loosely mounted on an eccentrically-mounted barrel a driven by chain gearing &c. from the crank shaft. The arms b<1> of the peg levers are controlled by a chain of pegged lags d, e on a barrel c, whilst the arms b<2> are formed with daggers b<3> and with projections b<4>, which engage notches f<2> on jack levers f<1> mounted on a fixed shaft &c. g when the corresponding arms b<1> are lowered, whereby as the barrel a rotates the jack levers are rocked and the corresponding healds are raised. Spring controlled locking-levers i then engage the notches f<3> of these jack levers and retain them in their raised positions until the arms b<1> of corresponding peg levers are raised, whereupon the daggers b<3> on the lowered arms b<2> engage beneath projections i' on the locking-levers ! i and disengage these levers from the notches f<3>, thus enabling the jack levers to move to their lowered position. This movement may be aided by springs m. The levers i engage notches f<4> in the lowered jack levers, a fixed stop bar l being also provided for these lowered levers. A roll k acts as a stop for the arms b<2>. The barrel c may be provided with a ratchet wheel engaged by a pawl, the hub of which is mounted on the barrel a, or the barrels a, c may be so geared together that if the loom is turned back the correct lag will always be in position. The jack levers may be connected to the shafts or cords by cords passing over pulleys &c., or they may be connected by hook joints &c. to streamers connecting them to pairs of co-operating levers for giving a straight lift to the healds, or the jack levers may be bent and connected directly to the healds.