other set comprises a minute hand gear and a minute detecting gear the two sets of gears are concentrically mounted for rotation and the minute detecting gear is positioned between the minute gear and the one set of gears the minute detecting gear has a contacting sliding contact with the minute gear the alarm signaling device further includes an alarm signaling time setting wheel having an axis of rotation parallel to that of the two sets of gears and a first gear and a second gear engaging the minute detecting gear and the hour detecting gear respectively application_number US 87782478 A description other objects and advantages will become more fully apparent as reference is had to the accompanying drawings wherein embodiments are illustrated referring now to fig1 4 the construction of a first embodiment will be explained a case 1 is formed of plastic material and provided with a projection 1a having a threaded hole a hole for rotatably guiding an extending boss 12a of the hour hand gear 12 a hole for rotatably guiding an alarm signaling time setting wheel 18 a boss for supporting a spindle 2a of an intermediate hour wheel 11 and a boss for supporting a spindle of a time adjusting gear 14 a middle frame 2 is formed of plastic material having holes for rotatably guiding an intermediate spindle 7 and an upwardly extending boss 9b of the minute hand gear 9 idle holes through which an alarm signaling time setting wheel 18 and a spindle of time adjusting gear 14 and a shaft 2a for rotatably mounting the intermediate hour wheel 11 a cover 3 is formed of plastic material having holes for rotatably guiding a spindle 6 for mounting the second hand gear 5 the intermediate spindle.