GB140668A - Improvements in and connected with clocks - Google Patents

Abstract

140,668. Watson, T., and Webb, C. F. June 17, 1919. Escapements; pendulums; balances; driving- mechanism, weiglit. - A balance-arm A with adjustable weights at each end is combined with pallets B, C and pivots E which roll to and fro in curved slots G, in the fixed frame as the balance swings. The slots are preferably circular arcs struck from the axis of the escape-wheel, so that as the balance swings, a point on it describes a hypo-cycloidal arc. The slots G may be made in a stirrup L suspended from the axis of the escapewheel, as shown in Fig. 3. With this arrangement of rolling pivots, it is not essential that the clock be accurately levelled. The balance-arm may be horizontal or vertical when at rest. In the horizontal form, the weights are arranged eccentrically on the arm, which bears in a block R, Fig. 3, and is rotated to regulate the timing. In the vertical form, the timing is regulated by adjusting the positions of the weights on the arm. The escapement may be applied to various types of clock, but is particularly applicable to that type in which the case slides on vertical guides one of which has rack teeth engaging a pinion, so that the weight of the case drives the clock-work.