Patent ID: 8460556

Claim:
A bacteria eliminator for removing bacteria from water supplied from a water main or other water supply means, comprising a flow passage, a detection section, a UV filament lamp, and a control section, the flow passage allowing the passage of water sent from the water supply means, the detection section sending detection signals corresponding to flow amount of the water to the control section, and the UV filament lamp generating ultra violet light, wherein the control section has: (1) a function of causing electrical current for pre-heating to flow in the UV filament lamp when the UV filament lamp is not lit; (2) a function of lighting the UV filament lamp according to detection signals from the detection section; wherein the UV filament lamp comprises a filament and a plate enclosed by a cover, the plate initially coated with mercury amalgam, wherein the filament and the plate are electrically connected to the control section, and wherein the UV filament lamp generates ultra violet light by emitting thermoelectrons from the filament to the plate and into mercury in a vapor state enclosed in the cover; wherein the cover is constructed from ultraviolet-ray transmitting glass; wherein the control section is configured to use, as minimum electric current value for the pre-heating, electric current value which maintains the vapor state of the mercury in the UV filament lamp; and wherein the control section is configured to use, as maximum electric current value for the pre-heating, electric current value such that the thermoelectron discharge amount from the filament to the plate is sufficiently low to avoid overheating of the UV filament lamp to avoid damage to the UV filament lamp even if water supplied from the water main or the other water supply means passes through the flow passage.