초록 ▼

A temperature-controlled laboratory heating apparatus consisting of a flexible electrical heater wrapped around the exterior surface of a conventional glass or metal beaker and permanently encased within a rubber molding forming an insulating ring around it. The heater is electrically connected to a

A temperature-controlled laboratory heating apparatus consisting of a flexible electrical heater wrapped around the exterior surface of a conventional glass or metal beaker and permanently encased within a rubber molding forming an insulating ring around it. The heater is electrically connected to a power source through an integrated-circuit temperature control panel. A thermistor is mounted against the outside surface of the beaker within the rubber molding and is connected to the control panel to regulate the flow of current through the electrical heater to reach and maintain the temperature set by the user. In one embodiment of the invention, the current through the heater is automatically regulated to optimize the time required to heat the liquid in the beaker to the desired temperature and to then deliver trickle currents, as needed, to minimize fluctuations from the set-point.

대표청구항 ▼

An apparatus for heating a liquid to a set-point temperature and for automatically maintaining that temperature, comprising: (a) a beaker made of thermally conductive material; (b) an electric heater wrapped around and affixed to the outside wall of said beaker; (c) electrical means for energizing s

An apparatus for heating a liquid to a set-point temperature and for automatically maintaining that temperature, comprising: (a) a beaker made of thermally conductive material; (b) an electric heater wrapped around and affixed to the outside wall of said beaker; (c) electrical means for energizing said electric heater; (d) temperature sensing means in contact with and thermally coupled to the outer surface of said beaker for developing a signal corresponding to the temperature of the beaker; (e) electronic means connected to said temperature sensing means for receiving a signal therefrom indicative of the temperature of the beaker and including means for comparing the signal so received to a set-point temperature corresponding to a temperature chosen by a user and for activating said electrical means for energizing said electric heater when the temperature corresponding to the signal is below the set-point temperature; and (f) a molding bonded to the outer surface of said beaker and formed around said electric heater and said temperature sensing means, wherein said molding completely covers the electric heater and the temperature sensing means and permanently bonds the heater and the temperature sensing means to the outer surface of the beaker; wherein said electronic means for comparing the signal developed by said temperature sensing means to a set-point temperature and for activating said electrical means for energizing said electric heater consists of an integrated circuit comparator connected to said temperature sensing means, to a rheostat for adjusting the set-point temperature, and to a triac device serving as a switch in said electrical means for controlling the current flow through said electric heater.