Abstract: The present disclosure relates to a filter. According to the present disclosure, there is provided a filter including: an upper body whose interior is filled with a filter medium; a lower body located under the upper body in such a manner as to be open on top and bottom thereof; and an escape prevention member located inside the lower body to allow sludge and a fluid to be introduced into the lower body and to prevent the sludge from escaping from the lower body, wherein the escape prevention member may include: a support plate fixed to the inside of the lower body and having a through hole formed at the center thereof; a center pipe fixed to top of the support plate and having a lower hole formed on the bottom thereof in such a manner as to communicate with the through hole and at least one or more connection holes formed on one side thereof; and a backflow prevention ball movable inside the center pipe in such a manner as to selectively open and close the lower hole to prevent the fluid from flowing back.

Abstract: Disclosed herein is a plunger switch for electric appliances, which is mounted to an electric appliance to control a lamp, a motor, a heater, etc. and has enhanced safety and electrical and mechanical properties, thus maintaining the original condition of the switch without reduction of elasticity or deformation of the switch, even if the switch is repeatedly used. Thereby, the operational reliability is increased and malfunctions caused by arc discharge are prevented. Unlike the sliding structure which does not use another separate contact point, this invention can be adapted to a high-current or high-temperature switch. Further, this invention has a hook, thus allowing easy assembly and replacement of the plunger switch to a proper position on an electric appliance.