Abstract: A smoke alarm having a layered structure includes a case, a smoke detecting unit, and a layering plate. The smoke detecting unit is disposed in the case, and includes a smoke collecting box and a control module electrically connected to the smoke collecting box. The layering plate is disposed in the case. The layering plate defines an upper layer space and a lower layer space in the case, the upper layer space is a smoke guiding space, and the smoke collecting box is accommodated in the upper layer space to facilitate smoke-containing air to flow to the smoke collecting box. The lower layer space is a module mounting space, and the control module is accommodated in the lower layer space to facilitate mounting of a sub-module of the control module that is detachable.

Abstract: A one-time activation smoke alarm includes a smoke alarm body and a wall-hanging base. The smoke alarm body includes a case and a sliding sheet. An engaging recessed slot and a supporting protrusion platform are respectively formed on two sides of a bottom of the case. The sliding sheet is slidably disposed on the supporting protrusion platform, and a front end of the sliding sheet has a pressed protrusion portion that extends into the engaging recessed slot. An engaging protrusion platform is formed on the wall-hanging base, and at least one abutting protrusion portion protrudes outward from a periphery of the engaging protrusion platform. The engaging protrusion platform and the engaging recessed slot are capable of being engaged and fixed together such that the abutting protrusion portion abuts the pressed protrusion portion and the smoke alarm body activates a detection function.

Abstract: A smoke detecting device includes a main body, a light-emitter, a first light-receiver, and a second light-receiver. The main body includes a smoke detecting chamber formed therein. The light-emitter is located within the smoke detecting chamber. The first light-receiver is located within the smoke detecting chamber. An optical axis of the first light-receiver and an optical axis of the light-emitter cooperatively define a first scattering angle there-between. The second light-receiver is located within the smoke detecting chamber. An optical axis of the second light-receiver and an optical axis of the light-emitter corporately define a second scattering angle there-between. The second light-receiver is closer to the light-emitter than to the first light-receiver. The second scattering angle is smaller than the first scattering angle.

Abstract: A button structure is provided for installing to a casing of an electronic device having a button opening. The button structure is flexible and comprises an engaging portion, a button portion, a first alignment portion, a second alignment portion and a hollow sleeve. The engaging portion is disposed at a fixing end of the button structure. The button structure is connected to the inward side of the casing through the engaging portion. The button portion is disposed at a free end of the button structure for aligning with the button opening of the casing. The button portion has a light guiding portion for neighboring to a light emitting diode. The first alignment portion and the second alignment portion are mounted on a first protrusion portion and a second protrusion portion of the casing respectively. The hollow sleeve is disposed axially movably to the fixing sleeve of the casing.

Abstract: A button structure is provided for installing to a casing of an electronic device having a button opening. The button structure is flexible and comprises an engaging portion, a button portion, a first alignment portion, a second alignment portion and a hollow sleeve. The engaging portion is disposed at a fixing end of the button structure. The button structure is connected to the inward side of the casing through the engaging portion. The button portion is disposed at a free end of the button structure for aligning with the button opening of the casing. The button portion has a light guiding portion for neighboring to a light emitting diode. The first alignment portion and the second alignment portion are mounted on a first protrusion portion and a second protrusion portion of the casing respectively. The hollow sleeve is disposed axially movably to the fixing sleeve of the casing.

Abstract: A smoke detector is adapted to be coupled to a fire monitoring unit, and includes a power consuming unit and a power supply unit. The power consuming unit is adapted to be coupled electrically to the fire monitoring unit so as to draw electric power therefrom. The power supply unit is coupled electrically to the power consuming unit, and is operable so as to supply electric power to the power consuming unit when the electric power from the fire monitoring unit is cut-off.