Patent GB-166075-A (GB)
Title: Improvements in leaf-turners for music, books, and the like
IPC: B42D9/08
Filed: 1920-10-26
Abstract: 166,075. Burton, E., and Norris, L. Oct. 26, 1920. Leaf-turners.-Relates to apparatus of the kind that is adjustably carried on a vertical support capable of being detachably mounted on a piano, book rest or the like, and consists in utilizing the mechanism for rotating the leaf-turning arms f, f<1>, f<2> in one direction for the purpose of rotating them in the reverse direction, the arms being loosely mounted on a vertical spindle d ana adapted to be rotated in succession against spring resistance by pedal-actuated mechanism. The music &c. is inserted between a split tube band a spring-pressed plate c carried by a bracket c<1>, the parts c', b being carried on the leaf-turner casing a. The arms carry transparent clips f<6> and are rotated by means of a disc h carrying a toothed pinion n in mesh with a rack q which is moved by Bowden-wire or other mechanism against a spring r. The disc h carries pawls j, k normally projected from recesses by springs. The disc h is shrouded for about half its circumference by the cam-flange m<1> of a housing m, the parts m<1> terminating in horn-like extensions m<2>, m<3> which turn the pawls on their pivots when the disc h is turned about the spindle d. The horn m<2> is juxtaposed with the under face of the housing m, but the horn m<3> stands away from this face and is a continuation of the edge of the flange m<1>. The points j<1>, k<1> of the pawls j, k are offset at j<2>, k<2> to permit the pawls to move along the horns m<2>, m<3> when in the projected position. In operation, on pressing the pedal, the rack q moves to the right until a stop q<3> passes clear of a lug f<4> on the front arm f, which is then free to move. Bv this time the disc h will have been turned sumoiently for the point of the pawl j to pass beyond the end of the flange m<1> and to engage the inner end of the arm f, which is swung through a semi-circle by the continued rotation of the disc h. By the time the pedal lever has completed its stroke, the stop q<3> has moved in front of a lug f<3> on the arm f<1>, while the pawl j has pressed the arm f into engagement with the left-hand end of a slidable member concentric with the flange m', causing the other end of the member to move the arms f<1>, f<2> into the position previously occupied by the arms f, f<1>. The leafturning movement is repeated at each stroke of the pedal, the pawl slipping past the inner end of the arm just operated at each return stroke. The arms can also be turned back in succession at pleasure by bringing the pawl k into action. The selection of the pawl j or k is effected from the pedal lever t which works in a gate with offset slots v<1>, v<2>, the lever t being pivoted at t' with stifficient play to allow it to travel in either slot. Supposing it is required to turn back a leaf, the lever t is deflected from the slot v' to the slot v<2>, and further upward movement gives the disc h an additional turn through a semicircle which causes the pawl k to pick up the arm which was last turned over. This operation can be repeated on other arms by pressing the pedal in the slot v<2> and releasing it. If it is desired to turn the same leaf to and fro, the pedal t is not pressed right home not entirely released; by this means first one pawl and then the other can be made to move the same arm to and fro.