Heating unit for disinfecting purposes

Abstract

An electrically energized heater is provided which has particular application as a dry disinfecting and sterilizing device for items such as soft lenses, dental handpieces, baby bottles, or the like, which cannot be placed in sterilizing solutions, and which cannot be subjected to excessive temperatures. The unit includes a housing, and a heat conductive substance such as wax, oil, or both, contained in the housing and used as a uniform heat transfer medium between electrical heating elements in the housing and the surface of a well which also is supported in the housing. The heater is generally applicable, and may be used to advantage, when it is desired to raise the temperature of an object or material to a particular disinfecting or sterilizing temperature for a given time period, and then to allow the temperature to cool down and return to ambient temperature condition, all without exceeding a critical temperature level, and without unnecessarily restricting the time period at which the particular disinfecting or sterilizing temperature is maintained. This is achieved in the heater of the invention by providing a manually resettable thermostatic switch immersed in the heat conductive substance which snaps off at the end of the given time period, and by also providing an automatic thermostatic switch immersed in the heat conductive substance and connected in series with the manual switch. The automatic thermostatic switch switches on and off during the given time period to hold the temperature below the critical level.