Abstract: A casing includes an elongated opening, an alarm device having a buzzer, a battery unit and a circuit unit to connect the battery unit to the buzzer, a time setting wheel and a conductive plate which has a first end connected to a first terminal of the battery unit, a second end abutting with the time setting wheel, a third end connected to a first contact point of the circuit board, and a fourth end above a second contact point of the circuit unit. The alarm device is actuated by a switch button assembly that includes a lever, which is made of a resilient, insulative material, pivotally mounted in the elongated opening and having a first end and a second end transversely passing the elongated opening to extend out of the casing.

Abstract: A switch includes a first plate with an upper edge and a lower edge. A sectoral recess is formed in the first plate extending from the upper edge. A curved groove is formed through the sectoral recess. A second plate has a latch and a projection extending from the second plate in a direction opposite the other. The second plate is provided in the sectoral recess with the latch slidably engaging in the curved groove of sectoral the recess. The second plate can move sideways in the sectoral recess.

Abstract: A switch button assembly includes a casing having a front, a rear wall and a side wall interconnecting the front and rear walls. The side wall has an opening through it. The rear wall has a protrusion extending perpendicularly into the casing adjacent to the opening of the side wall. A first plate has a central hole, an arched notch along the periphery and a plurality of claw-like member extending from the periphery of a bottom face. A second plate has a central shaft with a latch at its free end and latched into the claw-like members through the central hole of the first plate. The second plate further includes a projection that extends movably into the arched notch of the first plate. The second plate can rotate with respect to the first plate where the projection of the second plate engages with the protrusion of the rear wall.

Abstract: A circular plate used in a time setting device has a through-hole, a plurality of arched protrusions extending downward from the bottom of the same and a pair of arched projections extending upward from the periphery of the through-hole. Each arched protrusion has a first edge spaced parallelly apart from the bottom of the circular plate and a pair of second edges which converge to the free ends of the first edge.