Apparatus for controlling an air inlet valve for a solid fuel burner

An apparatus for controlling flow of air through an air inlet in a solid fuel burner, the apparatus comprising:

• a. a mechanical temperature sensor for sensing temperature within the solid fuel burner, the sensor comprising first and second elongate parts, the first elongate part having a first end that moves linearly in a direction of a length of the first elongate part, due to a difference in thermal expansion coefficients of the materials of the first and second elongate parts, in response to a change in the sensed temperature;
• and
• b. a movable valve member for controlling the flow of air through the air inlet, the moveable valve member being coupled to the first end of the first elongate part so as to close or restrict the air inlet as the sensed temperature increases,
• wherein a second end of the first elongate part is fixed relative to a second end of the second elongate part,
• wherein the first and second elongate parts extend in a parallel direction, with the positions of the second ends of the first and second elongate parts being fixed relative to one another in said parallel direction, and
• wherein the second elongate part comprises an elongate tube within which the first elongate part is located, the first end of the first elongate part projecting from the first end of the tube.

An apparatus for controlling flow of air through an air inlet in a solid fuel burner, the apparatus comprising:

• a. a mechanical temperature sensor for sensing temperature within the solid fuel burner, the sensor comprising first and second elongate parts, the first elongate part having a first end that moves linearly in a direction of a length of the first elongate part, due to a difference in thermal expansion coefficients of the materials of the first and second elongate parts, in response to a change in the sensed temperature;
• and
• b. a movable valve member for controlling the flow of air through the air inlet, the moveable valve member being coupled to the first end of the first elongate part so as to close or restrict the air inlet as the sensed temperature increases,
• wherein a second end of the first elongate part is fixed relative to a second end of the second elongate part,
• wherein the first and second elongate parts extend in a parallel direction, with the positions of the second ends of the first and second elongate parts being fixed relative to one another in said parallel direction, and
• wherein the second elongate part comprises one or more rods extending parallel to the first elongate part.

An apparatus for controlling flow of air through an air inlet in a solid fuel burner, the apparatus comprising:

• a. a mechanical temperature sensor for sensing temperature within the solid fuel burner, the sensor comprising first and second elongate parts, the first elongate part having a first end that moves linearly in a direction of a length of the first elongate part, due to a difference in thermal expansion coefficients of the materials of the first and second elongate parts, in response to a change in the sensed temperature;
• and
• b. a movable valve member for controlling the flow of air through the air inlet, the moveable valve member being coupled to the first end of the first elongate part so as to close or restrict the air inlet as the sensed temperature increases,
• wherein a second end of the first elongate part is fixed relative to a second end of the second elongate part, and
• wherein the first elongate part has a low coefficient of thermal expansion relative to the second elongate part.

An apparatus for controlling flow of air through an air inlet in a solid fuel burner, the apparatus comprising:

• a. a mechanical temperature sensor for sensing temperature within the solid fuel burner, the sensor comprising first and second elongate parts, the first elongate part having a first end that moves linearly in a direction of a length of the first elongate part, due to a difference in thermal expansion coefficients of the materials of the first and second elongate parts, in response to a change in the sensed temperature;
• and
• b. a movable valve member for controlling the flow of air through the air inlet, the moveable valve member being coupled to the first end of the first elongate part so as to close or restrict the air inlet as the sensed temperature increases,
• wherein the moveable valve member is coupled to the first end of the first elongate part by a lever mechanism arranged to amplify movement of the first end of the first elongate part, the lever mechanism comprising at least first and second levers coupled together such that the second lever amplifies motion of the first lever.

An apparatus for controlling flow of air through an air inlet in a solid fuel burner, the apparatus comprising:

• a. a mechanical temperature sensor for sensing temperature within the solid fuel burner, the sensor comprising first and second elongate parts, the first elongate part having a first end that moves linearly in a direction of a length of the first elongate part, due to a difference in thermal expansion coefficients of the materials of the first and second elongate parts, in response to a change in the sensed temperature;
• and
• b. a movable valve member for controlling the flow of air through the air inlet, the moveable valve member being coupled to the first end of the first elongate part so as to close or restrict the air inlet as the sensed temperature increases,
• wherein the moveable valve member is coupled to the first end of the first elongate part by a mechanism arranged to amplify movement of the first end of the first elongate part, the mechanism being arranged to prevent further movement of the movable valve member when the sensed temperature is above a high temperature at which the valve member is in a closed or restricted position.

An apparatus for controlling the flow of air through an air inlet in a solid fuel burner, the apparatus comprising:

• a. a mechanical temperature sensor for sensing temperature within the solid fuel burner, and
• b. a movable valve member for controlling the flow of air through the air inlet, the movable valve member being coupled to the mechanical temperature sensor so as to close or restrict the air inlet as the sensed temperature increases;
• wherein the sensor comprises an elongate part having a moveable end that moves linearly in the direction of the length of the elongate part by virtue of thermal expansion or contraction of the material of the elongate part in response to a change in the sensed temperature;
• and
• wherein the movable valve member is coupled to the moveable end of the elongate part, and
• wherein the elongate part comprises copper, brass or stainless steel.