Engine timer for cold-start advance

An engine timer comprising a predetermined rotary shaft (22) to which a driving wheel (1) is attached, the driving wheel (1) having one lateral portion at which a driven wheel (2) is arranged and having the other lateral portion at which a pair of centrifugal weights (3, 3) are arranged, respectively, each of the paired centrifugal weights (3, 3) being urged in a centripetal direction by a weight-return spring (5) composed of a compression coil spring, there being provided between the driving wheel (1) and the driven wheel (2) an eccentric cam mechanism (4) which is interlockingly connected to the pair of centrifugal weights (3, 3), wherein

• a force of unbalance between a centrifugal force of each of the paired centrifugal weights (3, 3) and an urging force of the weight-return spring (5) operating the respective centrifugal weights (3, 3), when each of the centrifugal weights (3, 3) moves in a centrifugal direction, it advances the driven wheel (2) with respect to the driving wheel (1) through the eccentric cam mechanism (4) and when each of the paired centrifugal weights (3, 3) moves in a centripetal direction, it lags the driven wheel (2) with respect to the driving wheel (1) through the eccentric cam mechanism (4), and wherein
• each of the paired centrifugal weights (3, 3) is interlockingly connected to an advancing spring (6), composed of a compression coil spring, which is interlockingly connected to a temperature-sensing operation means (7), when starting the engine during a cold term, the advancing spring (6) being maintained extensible based on a state of the temperature-sensing operation means (7), in which the temperature-sensing means (7) senses a temperature to operate, and exerting a spring force which pushes and widens the paired centrifugal weights (3, 3) to an advancing position (Ac) for cold-staring the engine and while the engine is warm, the advancing spring (6) being held contracted based on another state of the temperature-sensing operation means (7), in which the temperature-sensing operation means (7) senses a temperature to operate, so that the spring force of the advancing spring (6) does not act on the pair of centrifugal weights (3, 3),
• a shape memory spring (8) of a compression coil spring being used for the temperature-sensing operation means (7), the shape memory spring (8) and the advancing spring (6) being interposed between the pair of centrifugal weights (3, 3) in a position concentric with the weight-return spring (5).