Abstract: A solenoid valve includes a housing including a channel, a single-acting through hole, a double-acting through hole, a spring biased spool in the channel, a lateral outlet communicating with the double-acting through hole, and a hole element passing through an edge of the channel to communicate with both the double-acting through hole and the channel; a switch on the housing and including an axial tunnel, a shaft in the tunnel, a lateral single-acting hole communicating with the tunnel, a double-acting hole communicating with the tunnel, and a linking hole perpendicular to the tunnel but not communicating therewith; a pilot valve on the switch; a base at a bottom of the housing, and a spring biased check valve at a lower opening of the housing and the base, the check valve communicating with the single-acting through hole.

Abstract: A clock is provided with an emergency lighting device which is composed of an electronic control apparatus, at least one light bulb, a battery, a plug, and a switch knob. The light bulb is located in a concave slot of the dial plate of the clock such that light bulb does not obstruct the movements of the second hand, the minute hand and the hour hand of the clock. The emergency lighting device is housed in the case of the clock. When a power outage takes place, the electronic control apparatus is triggered to turn on the light bulb.