US 7,064,303 B2 · Tubular heater and method of manufacture

Abstract

A tubular heater that is manually bendable to fit into a channel comprises a heating element positioned in an insulative material such as magnesium oxide and encased in a continuous inner nickel tubular sheathing. An outer sheathing, in a preferred embodiment, comprises a coil of copper with a nickel coating swaged such that the cross-section of a strand of the coil is generally rectangular. The invention also includes the method of manufacturing and method of use of the tubular heater. Alternate embodiments include an outer tubular sheath that has a multiplicity of slits extending in a circumferential direction through the outer sheathing and the outer sheathing swaged directly on the inner sheathing. A further embodiment includes the outer tubular sheathing formed from a multiplicity of individual rings, the outer sheath could be swaged directly on the inner sheath.

Claims17

Dependent claims

A bendable tubular heater for use in an injection molding component, the heater comprising:

a flexible heating element wire having two ends;
two electrical connectors, each one in electrical connection to one of the two ends;
a continuous tubular first metallic sheath, said first metallic sheath having an intermediate portion and two ends, the heating element wire extending through the intermediate portion of the metallic sheath;
insulative material surrounding and supporting the heating element wire within said first metallic sheath;
a second metallic sheath having a radial thickness and formed of at least one swaged helically wound coil, said shealth encasing and engaging the first metallic sheath, whereby a closed helical slit extends entirely thru the radial thickness of the second metallic sheath providing improved bendability.

2 more elements

Dependencies are inferred from the claim text.

Tubular heater and method of manufacture

Life of this patent

Tubular heater and method of manufacture

Life of this patent

Abstract

Claims17