Thermostatically controlled plural heat output portable electric space heater

A portable electric heater, comprising a case defining an enclosure having separated air flow openings adjacent the opposite upper and lower ends thereof, respectively,

• heating element means mounted in the case enclosure between the upper and lower openings,
• air moving means for drawing outside air into the case enclosure through the upper opening for passage over the heating element means and for discharge out the lower opening,
• thermostat means for sensing the temperature of the air passing through the case enclosure and having a first set of control contacts closed during a heat demand situation and opened at a first predetermined temperature at a heat satisfied situation and a second set of control contacts closed normally and opened only during an overheat situation occurring at a second predetermined temperature, higher than said first predetermined temperature, control circuit means including said heating element means, thermostat means and said air moving means, the thermostat means operable for energizing the heating element means and air moving means, respectively, at high output thereof when the temperature of the air passing through the case enclosure is less than said first predetermined temperature, during the heat demand situation, and for energizing the heating element means at a substantially lower heat output and effectively deenergizing the air moving means when the temperature of the air passing through said case enclosure reaches said first predetermined temperature, during the heat satisfied situation, whereby convective air flow only passes through the case enclosure from the lower opening over the heating element means for discharge from the heater casing out the upper opening, and the heating element means and the air moving means being deenergized completely when the temperature of the air passing through said case enclosure reaches said second predetermined temperature in the overheat situation.

A portable electric heater, comprising a case defining an enclosure having separated air flow openings adjacent the opposite upper and lower ends thereof, heating element means mounted in the case enclosure between the upper and lower openings, air moving means for drawing outside air into the case enclosure through the upper openings for passage over the heating element means and for discharge out the lower openings, a control switch having high heat and low heat operative settings, a thermostat for sensing ambient air passing through the case enclosure and having a set of control contacts closed during a heat demand situation and opened during a heat satisfied situation, control circuit means including the control switch and thermostat operable for energizing the heating element means and air moving means at high outputs thereof in both the high heat and the low heat operative control switch settings during the heat demand situation, and for energizing the heating element means and air moving means at modulated lower outputs in the high heat operative control switch setting during the heat satisfied situation, and for energizing the heating element means for only a modulated lowest heat output and effectively deenergizing the air moving means in the low heat operative control switch setting during the heat satisfied situation whereby convective air flow only passes through the case enclosure from the lower openings over the heating element means for discharge from the heater out the upper openings.

A portable electric heater including in combination:

• an outer casing defining an enclosure having an upper and lower end, said casing having separated air flow openings adjacent the upper and lower end, respectively, of said enclosure,
• heating element means mounted within said enclosure between the upper and lower openings,
• electrically operated air moving means for moving air into the enclosure through the upper opening, over the heating element means and out the lower opening,
• control switch means operable between inoperative and operative settings,
• a thermostat for sensing the temperature of the air passing through said enclosure and including contact means operable to a first state when the air temperature is below a first predetermined level during a heat demand condition and operable to a second state when the air temperature reaches said first predetermined level at a heat satisfied condition,
• control circuit means connectable to a source of electrical power and including said control switch means, said heating element means, said air moving means and said thermostat,
• said control circuit means being operable in a first mode when said control switch means is operated to said operative setting and the contact means of said thermostat are operated to said first state for energizing said heating element means to a high heat output level and said air moving means at a relatively high speed and in a second mode in response to the contact means of said thermostat being operated to said second state for energizing said heating element means to a substantially lower heat output level and for effectively deenergizing said air moving means, the air flow passing by convection into said enclosure through the lower opening, over said heating elements and out said upper opening in said last-mentioned mode of operation,
• said control circuit means being operated automatically between said first and second modes of operation in response to temperature changes of said air between said first predetermined level and below.

A portable electric heater including in combination:

• an outer casing defining an enclosure having an upper and lower end, said casing having separated air flow openings adjacent the upper and lower end, respectively, of said enclosure,
• heating element means mounted within said enclosure between the upper and lower openings,
• electrically operated air moving means for moving air into the enclosure through the upper opening, over the heating element means and out the lower opening,
• control switch means operable between inoperative and operative settings,
• a thermostat for sensing the temperature of the air passing through said enclosure and including contact means operable to a first state when the air temperature is below a first predetermined level during a heat demand condition and operable to a second state when the air temperature reaches said first predetermined level at a heat satisfied condition,
• control circuit means connectable to a source of electrical power and including said control switch means, said heating element means, said air moving means and said thermostat means,
• said control circuit means being operable in a first mode when said control switch means is operated to said operative setting and the contact means of said thermostat are in said first state for energizing said heating element means to a high heat output level and said air moving means at a relatively high speed, and in a second mode in response to the contact means of said thermostat being operated to said second state for energizing said heating element means to a low level heat output level and said air moving means at a slow speed, said control circuit means being operated automatically between said first and second modes of operation in response to temperature changes of said air between said first predetermined level and below when said control switch means is in said operative setting.