Variable pitch resistance coil heater
AssigneeWatlow Electric Manufacturing Company
InventorsScott Boehmer, Dennis P. Long, Rolando O. Juliano
Life of this patent
Estimating the term…
Abstract
A resistance element includes a resistance coil having a first end and a second end opposite the first end. The resistance coil defines a plurality of first portions defining a first constant diameter and a plurality of second portions defining a second constant diameter smaller than the first diameter. At least one of the first portions and the second portions has a continuously variable pitch. The resistance coil may also further define two third portions, each third portion being disposed adjacent to a corresponding first or second end. The resistance element may be disposed between first and second conducting pins in a heater.
Claims20
A resistance heating element comprising:
- a resistance coil having a first end and a second end opposite the first end, the resistance coil defining:
- a plurality of first portions defining a first constant diameter;
- and
- a plurality of second portions defining a second constant diameter smaller than the first diameter,
- wherein at least one of the first portions and the second portions has a continuously variable pitch.
A resistance heating element comprising:
- a resistance coil having a first end and a second end opposite the first end, the resistance coil defining:
- a plurality of first portions defining a first constant diameter;
- a plurality of second portions defining a second constant diameter smaller than the first diameter;
- and
- two third portions, each third portion disposed adjacent to a corresponding one of the first and second ends, each third portion having a variable diameter,
- wherein at least one of the first portions and the second portions has a continuously variable pitch.
A heater comprising:
- a first conducting pin;
- a second conducting pin;
- and
- a resistance coil disposed between the first and second conducting pins, the resistive coil including a first end and a second end opposite the first end and the resistive coil defining:
- a plurality of first portions defining a first constant diameter;
- a plurality of second portions defining a second constant diameter smaller than the first constant diameter, at least one of the second portions disposed between two different ones of the plurality of first portions;
- and
- two third portions, each third portion disposed adjacent to a corresponding one of the first and second ends, wherein one third portion is connected between the first conducting pin and one of the first portions that is closest to the first conducting pin and the other third portion is connected between the second conducting pin and one of the first portions that is closest to the second conducting pin,
- wherein at least one of the first portions, the second portions, and the third portions has a continuously variable pitch.
Dependencies are inferred from the claim text.